Nokogiri is an open source XML and HTML library for Ruby. Nokogiri `< v1.13.4` contains an inefficient regular expression that is susceptible to excessive backtracking when attempting to detect encoding in HTML documents. Users are advised to upgrade to Nokogiri `>= 1.13.4`. There are no known workarounds for this issue.

Koa is expressive middleware for Node.js using ES2017 async functions. Prior to versions 0.21.2, 1.7.1, 2.15.4, and 3.0.0-alpha.3, Koa uses an evil regex to parse the `X-Forwarded-Proto` and `X-Forwarded-Host` HTTP headers. This can be exploited to carry out a Denial-of-Service attack. Versions 0.21.2, 1.7.1, 2.15.4, and 3.0.0-alpha.3 fix the issue.

parse-duraton is software that allows users to convert a human readable duration to milliseconds. Versions prior to 2.1.3 are vulnerable to an event loop delay due to the CPU-bound operation of resolving the provided string, from a 0.5ms and up to ~50ms per one operation, with a varying size from 0.01 MB and up to 4.3 MB respectively, and an out of memory that would crash a running Node.js application due to a string size of roughly 10 MB that utilizes unicode characters. Version 2.1.3 contains a patch.

Loofah is a general library for manipulating and transforming HTML/XML documents and fragments, built on top of Nokogiri. Loofah < 2.19.1 contains an inefficient regular expression that is susceptible to excessive backtracking when attempting to sanitize certain SVG attributes. This may lead to a denial of service through CPU resource consumption. This issue is patched in version 2.19.1.

Znuny before LTS 6.5.1 through 6.5.10 and 7.0.1 through 7.0.16 allows DoS/ReDos via email. Parsing the content of emails where HTML code is copied from Microsoft Word could lead to high CPU usage and block the parsing process.

rails-html-sanitizer is responsible for sanitizing HTML fragments in Rails applications. Certain configurations of rails-html-sanitizer < 1.4.4 use an inefficient regular expression that is susceptible to excessive backtracking when attempting to sanitize certain SVG attributes. This may lead to a denial of service through CPU resource consumption. This issue has been patched in version 1.4.4.

Marked is a markdown parser and compiler. Prior to version 4.0.10, the regular expression `block.def` may cause catastrophic backtracking against some strings and lead to a regular expression denial of service (ReDoS). Anyone who runs untrusted markdown through a vulnerable version of marked and does not use a worker with a time limit may be affected. This issue is patched in version 4.0.10. As a workaround, avoid running untrusted markdown through marked or run marked on a worker thread and set a reasonable time limit to prevent draining resources.

Marked is a markdown parser and compiler. Prior to version 4.0.10, the regular expression `inline.reflinkSearch` may cause catastrophic backtracking against some strings and lead to a denial of service (DoS). Anyone who runs untrusted markdown through a vulnerable version of marked and does not use a worker with a time limit may be affected. This issue is patched in version 4.0.10. As a workaround, avoid running untrusted markdown through marked or run marked on a worker thread and set a reasonable time limit to prevent draining resources.

The package css-what before 2.1.3 are vulnerable to Regular Expression Denial of Service (ReDoS) due to the usage of insecure regular expression in the re_attr variable of index.js. The exploitation of this vulnerability could be triggered via the parse function.

All versions of package url-regex are vulnerable to Regular Expression Denial of Service (ReDoS) which can cause the CPU usage to crash.

An issue has been discovered in GitLab affecting all versions starting from 13.9 before 14.8.6, all versions starting from 14.9 before 14.9.4, all versions starting from 14.10 before 14.10.1. GitLab was not correctly handling malicious text in the CI Editor and CI Pipeline details page allowing the attacker to cause uncontrolled resource consumption.

Signal K Server is a server application that runs on a central hub in a boat. Versions prior to 2.25.0 are vulnerable to an unauthenticated Regular Expression Denial of Service (ReDoS) attack within the WebSocket subscription handling logic. By injecting unescaped regex metacharacters into the `context` parameter of a stream subscription, an attacker can force the server's Node.js event loop into a catastrophic backtracking loop when evaluating long string identifiers (like the server's self UUID). This results in a total Denial of Service (DoS) where the server CPU spikes to 100% and becomes completely unresponsive to further API or socket requests. Version 2.25.0 contains a fix.

PraisonAI is a multi-agent teams system. Prior to version 4.5.90, MCPToolIndex.search_tools() compiles a caller-supplied string directly as a Python regular expression with no validation, sanitization, or timeout. A crafted regex causes catastrophic backtracking in the re engine, blocking the Python thread for hundreds of seconds and causing a complete service outage. This issue has been patched in version 4.5.90.

@hapi/content provided HTTP Content-* headers parsing. All versions of @hapi/content through 6.0.0 are vulnerable to Regular Expression Denial of Service (ReDoS) via crafted HTTP header values. Three regular expressions used to parse Content-Type and Content-Disposition headers contain patterns susceptible to catastrophic backtracking. This vulnerability is fixed in 6.0.1.

Picomatch is a glob matcher written JavaScript. Versions prior to 4.0.4, 3.0.2, and 2.3.2 are vulnerable to Regular Expression Denial of Service (ReDoS) when processing crafted extglob patterns. Certain patterns using extglob quantifiers such as `+()` and `*()`, especially when combined with overlapping alternatives or nested extglobs, are compiled into regular expressions that can exhibit catastrophic backtracking on non-matching input. Applications are impacted when they allow untrusted users to supply glob patterns that are passed to `picomatch` for compilation or matching. In those cases, an attacker can cause excessive CPU consumption and block the Node.js event loop, resulting in a denial of service. Applications that only use trusted, developer-controlled glob patterns are much less likely to be exposed in a security-relevant way. This issue is fixed in picomatch 4.0.4, 3.0.2 and 2.3.2. Users should upgrade to one of these versions or later, depending on their supported release line. If upgrading is not immediately possible, avoid passing untrusted glob patterns to `picomatch`. Possible mitigations include disabling extglob support for untrusted patterns by using `noextglob: true`, rejecting or sanitizing patterns containing nested extglobs or extglob quantifiers such as `+()` and `*()`, enforcing strict allowlists for accepted pattern syntax, running matching in an isolated worker or separate process with time and resource limits, and applying application-level request throttling and input validation for any endpoint that accepts glob patterns.

TF2 Item Format helps users format TF2 items to the community standards. Versions of `tf2-item-format` since at least `4.2.6` and prior to `5.9.14` are vulnerable to a Regular Expression Denial of Service (ReDoS) attack when parsing crafted user input. This vulnerability can be exploited by an attacker to perform DoS attacks on any service that uses any `tf2-item-format` to parse user input. Version `5.9.14` contains a fix for the issue.

The marked package before 0.3.4 for Node.js allows attackers to cause a denial of service (CPU consumption) via unspecified vectors that trigger a "catastrophic backtracking issue for the em inline rule," aka a "regular expression denial of service (ReDoS)."

An issue in the validate_email function in CTFd/utils/validators/__init__.py of CTFd 3.7.3 allows attackers to cause a Regular expression Denial of Service (ReDoS) via supplying a crafted string as e-mail address during registration.

Denial of service condition in M-Files Server in versions before 24.4.13592.4 and after 23.11 (excluding 24.2 LTS) allows unauthenticated user to consume computing resources.

minimatch is a minimal matching utility for converting glob expressions into JavaScript RegExp objects. Prior to version 10.2.3, 9.0.7, 8.0.6, 7.4.8, 6.2.2, 5.1.8, 4.2.5, and 3.1.4, nested `*()` extglobs produce regexps with nested unbounded quantifiers (e.g. `(?:(?:a|b)*)*`), which exhibit catastrophic backtracking in V8. With a 12-byte pattern `*(*(*(a|b)))` and an 18-byte non-matching input, `minimatch()` stalls for over 7 seconds. Adding a single nesting level or a few input characters pushes this to minutes. This is the most severe finding: it is triggered by the default `minimatch()` API with no special options, and the minimum viable pattern is only 12 bytes. The same issue affects `+()` extglobs equally. Versions 10.2.3, 9.0.7, 8.0.6, 7.4.8, 6.2.2, 5.1.8, 4.2.5, and 3.1.4 fix the issue.

A Denial of Service (DoS) condition has been discovered in GitLab CE/EE affecting all versions from 7.10 prior before 16.11.5, version 17.0 before 17.0.3, and 17.1 before 17.1.1. It is possible for an attacker to cause a denial of service using a crafted markdown page.

Inefficient Regular Expression Complexity (CWE-1333) in the AI Inference Anonymization Engine in Kibana can lead Denial of Service via Regular Expression Exponential Blowup (CAPEC-492).

minimatch is a minimal matching utility for converting glob expressions into JavaScript RegExp objects. Versions 10.2.0 and below are vulnerable to Regular Expression Denial of Service (ReDoS) when a glob pattern contains many consecutive * wildcards followed by a literal character that doesn't appear in the test string. Each * compiles to a separate [^/]*? regex group, and when the match fails, V8's regex engine backtracks exponentially across all possible splits. The time complexity is O(4^N) where N is the number of * characters. With N=15, a single minimatch() call takes ~2 seconds. With N=34, it hangs effectively forever. Any application that passes user-controlled strings to minimatch() as the pattern argument is vulnerable to DoS. This issue has been fixed in version 10.2.1.

jsdiff is a JavaScript text differencing implementation. Prior to versions 8.0.3, 5.2.2, 4.0.4, and 3.5.1, attempting to parse a patch whose filename headers contain the line break characters `\r`, `\u2028`, or `\u2029` can cause the `parsePatch` method to enter an infinite loop. It then consumes memory without limit until the process crashes due to running out of memory. Applications are therefore likely to be vulnerable to a denial-of-service attack if they call `parsePatch` with a user-provided patch as input. A large payload is not needed to trigger the vulnerability, so size limits on user input do not provide any protection. Furthermore, some applications may be vulnerable even when calling `parsePatch` on a patch generated by the application itself if the user is nonetheless able to control the filename headers (e.g. by directly providing the filenames of the files to be diffed). The `applyPatch` method is similarly affected if (and only if) called with a string representation of a patch as an argument, since under the hood it parses that string using `parsePatch`. Other methods of the library are unaffected. Finally, a second and lesser interdependent bug - a ReDOS - also exhibits when those same line break characters are present in a patch's *patch* header (also known as its "leading garbage"). A maliciously-crafted patch header of length *n* can take `parsePatch` O(*n*³) time to parse. Versions 8.0.3, 5.2.2, 4.0.4, and 3.5.1 contain a fix. As a workaround, do not attempt to parse patches that contain any of these characters: `\r`, `\u2028`, or `\u2029`.

A vulnerability in the `preprocess_string()` function of the `transformers.testing_utils` module in huggingface/transformers version v4.48.3 allows for a Regular Expression Denial of Service (ReDoS) attack. The regular expression used to process code blocks in docstrings contains nested quantifiers, leading to exponential backtracking when processing input with a large number of newline characters. An attacker can exploit this by providing a specially crafted payload, causing high CPU usage and potential application downtime, effectively resulting in a Denial of Service (DoS) scenario.

Apollo Server is an open-source, spec-compliant GraphQL server that's compatible with any GraphQL client, including Apollo Client. In versions from 2.0.0 to 3.13.0, 4.2.0 to before 4.13.0, and 5.0.0 to before 5.4.0, the default configuration of startStandaloneServer from @apollo/server/standalone is vulnerable to denial of service (DoS) attacks through specially crafted request bodies with exotic character set encodings. This issue does not affect users that use @apollo/server as a dependency for integration packages, like @as-integrations/express5 or @as-integrations/next, only direct usage of startStandaloneServer.

Async <= 2.6.4 and <= 3.2.5 are vulnerable to ReDoS (Regular Expression Denial of Service) while parsing function in autoinject function. NOTE: this is disputed by the supplier because there is no realistic threat model: regular expressions are not used with untrusted input.

Elysia is a Typescript framework for request validation, type inference, OpenAPI documentation and client-server communication. Prior to 1.4.26 , t.String({ format: 'url' }) is vulnerable to ReDoS. Repeating a partial url format (protocol and hostname) multiple times cause regex to slow down significantly. This vulnerability is fixed in 1.4.26.

Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to 9.5.0-alpha.14 and 8.6.11, a malicious client can subscribe to a LiveQuery with a crafted $regex pattern that causes catastrophic backtracking, blocking the Node.js event loop. This makes the entire Parse Server unresponsive, affecting all clients. Any Parse Server deployment with LiveQuery enabled is affected. The attacker only needs the application ID and JavaScript key, both of which are public in client-side apps. This only affects LiveQuery subscription matching, which evaluates regex in JavaScript on the Node.js event loop. Normal REST and GraphQL queries are not affected because their regex is evaluated by the database engine. This vulnerability is fixed in 9.5.0-alpha.14 and 8.6.11.

multipart is a fast multipart/form-data parser for python. Prior to 1.2.2, 1.3.1 and 1.4.0-dev, the parse_options_header() function in multipart.py uses a regular expression with an ambiguous alternation, which can cause exponential backtracking (ReDoS) when parsing maliciously crafted HTTP or multipart segment headers. This can be abused for denial of service (DoS) attacks against web applications using this library to parse request headers or multipart/form-data streams. The issue is fixed in 1.2.2, 1.3.1 and 1.4.0-dev.

An issue pertaining to CWE-1333: Inefficient Regular Expression Complexity (4.19) was discovered in mscdex ssh2 v1.17.0.

seroval facilitates JS value stringification, including complex structures beyond JSON.stringify capabilities. In versions 0.2.0 through 1.4.0, overriding RegExp serialization with extremely large patterns can exhaust JavaScript runtime memory during deserialization. Additionally, overriding RegExp serialization with patterns that trigger catastrophic backtracking can lead to ReDoS (Regular Expression Denial of Service). This issue has been fixed in version 1.4.1.

lib/DatabaseLayer.py in cve-search before 4.1.0 allows regular expression injection, which can lead to ReDoS (regular expression denial of service) or other impacts.

Versions of the package markdown-it from 13.0.0 and before 14.1.1 are vulnerable to Regular Expression Denial of Service (ReDoS) due to the use of the regex /\*+$/ in the linkify function. An attacker can supply a long sequence of * characters followed by a non-matching character, which triggers excessive backtracking and may lead to a denial-of-service condition.

Flag Forge is a Capture The Flag (CTF) platform. Versions 2.3.2 and below have a Regular Expression Denial of Service (ReDoS) vulnerability in the user profile API endpoint (/api/user/[username]). The application constructs a regular expression dynamically using unescaped user input (the username parameter). An attacker can exploit this by sending a specially crafted username containing regex meta-characters (e.g., deeply nested groups or quantifiers), causing the MongoDB regex engine to consume excessive CPU resources. This can lead to Denial of Service for other users. The issue is fixed in version 2.3.3. To workaround this issue, implement a Web Application Firewall (WAF) rule to block requests containing regex meta-characters in the URL path.

Solidus is a free, open-source ecommerce platform built on Rails. Versions of Solidus prior to 3.1.4, 3.0.4, and 2.11.13 have a denial of service vulnerability that could be exploited during a guest checkout. The regular expression used to validate a guest order's email was subject to exponential backtracking through a fragment like `a.a.` Versions 3.1.4, 3.0.4, and 2.11.13 have been patched to use a different regular expression. The maintainers added a check for email addresses that are no longer valid that will print information about any affected orders that exist. If a prompt upgrade is not an option, a workaround is available. It is possible to edit the file `config/application.rb` manually (with code provided by the maintainers in the GitHub Security Advisory) to check email validity.

path-to-regexp turns path strings into a regular expressions. In certain cases, path-to-regexp will output a regular expression that can be exploited to cause poor performance. Because JavaScript is single threaded and regex matching runs on the main thread, poor performance will block the event loop and lead to a DoS. The bad regular expression is generated any time you have two parameters within a single segment, separated by something that is not a period (.). For users of 0.1, upgrade to 0.1.10. All other users should upgrade to 8.0.0.

jsx-slack is a package for building JSON objects for Slack block kit surfaces from JSX. The maintainers found the patch for CVE-2021-43838 in jsx-slack v4.5.1 is insufficient tfor protection from a Regular Expression Denial of Service (ReDoS) attack. If an attacker can put a lot of JSX elements into `<blockquote>` tag _with including multibyte characters_, an internal regular expression for escaping characters may consume an excessive amount of computing resources. v4.5.1 passes the test against ASCII characters but misses the case of multibyte characters. jsx-slack v4.5.2 has updated regular expressions for escaping blockquote characters to prevent catastrophic backtracking. It is also including an updated test case to confirm rendering multiple tags in `<blockquote>` with multibyte characters.

jsx-slack is a library for building JSON objects for Slack Block Kit surfaces from JSX. In versions prior to 4.5.1 users are vulnerable to a regular expression denial-of-service (ReDoS) attack. If attacker can put a lot of JSX elements into `<blockquote>` tag, an internal regular expression for escaping characters may consume an excessive amount of computing resources. jsx-slack v4.5.1 has patched to a regex for escaping blockquote characters. Users are advised to upgrade as soon as possible.

An exponential ReDoS (Regular Expression Denial of Service) can be triggered in the semver-regex npm package, when an attacker is able to supply arbitrary input to the test() method

An exponential ReDoS (Regular Expression Denial of Service) can be triggered in the uri-template-lite npm package, when an attacker is able to supply arbitrary input to the "URI.expand" method

A vulnerability classified as problematic was found in cronvel string-kit up to 0.12.7. This vulnerability affects the function naturalSort of the file lib/naturalSort.js. The manipulation leads to inefficient regular expression complexity. The attack can be initiated remotely. Upgrading to version 0.12.8 is able to address this issue. The name of the patch is 9cac4c298ee92c1695b0695951f1488884a7ca73. It is recommended to upgrade the affected component. The identifier of this vulnerability is VDB-217180.

GitLab has remediated an issue in GitLab CE/EE affecting all versions from 9.2 before 18.7.5, 18.8 before 18.8.5, and 18.9 before 18.9.1 that could have allowed an unauthenticated user to cause regular expression denial of service by sending specially crafted input to a merge request endpoint under certain conditions.

Date.parse in the date gem through 3.2.0 for Ruby allows ReDoS (regular expression Denial of Service) via a long string. The fixed versions are 3.2.1, 3.1.2, 3.0.2, and 2.0.1.

Anthropic's MCP TypeScript SDK versions up to and including 1.25.1 contain a regular expression denial of service (ReDoS) vulnerability in the UriTemplate class when processing RFC 6570 exploded array patterns. The dynamically generated regular expression used during URI matching contains nested quantifiers that can trigger catastrophic backtracking on specially crafted inputs, resulting in excessive CPU consumption. An attacker can exploit this by supplying a malicious URI that causes the Node.js process to become unresponsive, leading to a denial of service.

A Regular Expression Denial of Service (ReDOS) vulnerability was discovered in repo-git-downloader v0.1.1 when downloading crafted invalid git repositories.

A Regular Expression Denial of Service (ReDOS) vulnerability was discovered in validate-data v0.1.1 when validating crafted invalid emails.

A Regular Expression Denial of Service (ReDOS) vulnerability was discovered in scniro-validator v1.0.1 when validating crafted invalid emails.

A Regular Expression Denial of Service (ReDOS) vulnerability was discovered in underscore-99xp v1.7.2 when the deepValueSearch function is called.

A vulnerability was found in yarnpkg Yarn up to 1.22.22. It has been classified as problematic. Affected is the function explodeHostedGitFragment of the file src/resolvers/exotics/hosted-git-resolver.js. The manipulation leads to inefficient regular expression complexity. It is possible to launch the attack remotely. The patch is identified as 97731871e674bf93bcbf29e9d3258da8685f3076. It is recommended to apply a patch to fix this issue.