LiquidJS is a Shopify/GitHub Pages compatible template engine written in pure JavaScript. In versions 10.25.7 and below, the renderLimit option can be fully bypassed by a {% for %} (or {% tablerow %}) tag whose body is empty. The renderLimit option is documented in docs/source/tutorials/dos.md as the mechanism that "mitigates this by limiting the time consumed by each render() call." The per-iteration time check is reached only when the body contains at least one template node, so a template such as {%- for i in (1..N) -%}{%- endfor -%} iterates the full collection without ever consulting renderLimit. With a configured renderLimit of 50 ms, a single parseAndRenderSync call has been observed to consume 2.26 seconds (~45× over the limit) and scales linearly with N up to memoryLimit, allowing a low-privileged template author to wedge an event-loop thread for an attacker-chosen duration. Deployments that rely on a finite renderLimit for DoS protection (common in multi-tenant template-authoring environments) can still be forced by a single crafted template to monopolize a Node.js event-loop worker for attacker-controlled time, potentially stalling in-flight requests, with availability impact only. This issue has been fixed in version 10.26.0.

LiquidJS is a Shopify/GitHub Pages compatible template engine written in pure JavaScript. In versions 10.25.7 and below, the date filter's strftime implementation parses width specifiers like %9999999d and forwards the captured width unchecked into pad()/padStart(), leading to memory and render limit bypass. In src/util/underscore.ts, the pad loop performs unbounded string concatenation without consulting the Context's memoryLimit or renderLimit, so a single small template ({{ x | date: '%5000000d' }}) produces megabytes of output and unbounded CPU. The memoryLimit and renderLimit options the docs (src/liquid-options.ts:87-92) advertise as DoS controls — and which the docstring explicitly mentions for strftime — are entirely bypassed. Exploitation can cause large memory allocations, high CPU usage, or OOM crashes per render. This issue has been fixed in version 10.26.0.

LiquidJS is a Shopify/GitHub Pages compatible template engine written in pure JavaScript. In versions 10.25.7 and below, the built-in strip_html filter uses a regex containing four flawed lazy-quantified alternatives, leading to ReDoS via quadratic backtracking. When the input contains many <script, <style, or <!-- opener tokens without matching closers, the V8 regex engine performs O(N²) backtracking, blocking the Node.js event loop. A single ~350 KB request ('<script'.repeat(50000)) stalls the process for ~10 seconds; cost grows quadratically with input size. The default memoryLimit: Infinity does not bound regex CPU, and even when configured strip_html only charges str.length to the limit — the regex itself runs unbounded. A single unauthenticated request containing crafted untrusted input can cause severe event-loop blocking and CPU amplification that saturates Node.js workers while bypassing memoryLimit protections. This issue has been fixed in version 10.26.0.

LiquidJS is a Shopify / GitHub Pages compatible template engine in pure JavaScript. Prior to version 10.25.1, LiquidJS's `memoryLimit` security mechanism can be completely bypassed by using reverse range expressions (e.g., `(100000000..1)`), allowing an attacker to allocate unlimited memory. Combined with a string flattening operation (e.g., `replace` filter), this causes a V8 Fatal error that crashes the Node.js process, resulting in complete denial of service from a single HTTP request. Version 10.25.1 patches the issue.

LiquidJS is a Shopify / GitHub Pages compatible template engine in pure JavaScript. Prior to version 10.25.1, the `replace_first` filter in LiquidJS uses JavaScript's `String.prototype.replace()` which interprets `$&` as a back reference to the matched substring. The filter only charges `memoryLimit` for the input string length, not the amplified output. An attacker can achieve exponential memory amplification (up to 625,000:1) while staying within the `memoryLimit` budget, leading to denial of service. Version 10.25.1 patches the issue.

UniValue::read() in UniValue before 1.0.5 allow attackers to cause a denial of service (the class internal data reaches an inconsistent state) via input data that triggers an error.

SurrealDB versions before 1.1.0 fail to enforce recursion depth limits when parsing nested SurrealQL statements including IF, RELATE, and attribute access idioms. Authorized attackers can submit queries with excessive nesting depth to cause stack overflow and crash the server.

A Denial Of Service vulnerability exists in the safe-svg (aka Safe SVG) plugin through 1.9.4 for WordPress, related to unlimited recursion for a '<use ... xlink:href="#identifier">' substring.

CodeIgniter is a PHP full-stack web framework A vulnerability was found in the Language class that allowed DoS attacks. This vulnerability can be exploited by an attacker to consume a large amount of memory on the server. Upgrade to v4.4.7 or later.

XGrammar is an open-source library for efficient, flexible, and portable structured generation. Prior to version 0.1.21, XGrammar has an infinite recursion issue in the grammar. This issue has been resolved in version 0.1.21.

Nextcloud Server before 9.0.55 and 10.0.2 suffers from a Denial of Service attack. Due to an error in the application logic an authenticated adversary may trigger an endless recursion in the application leading to a potential Denial of Service.

A vulnerability in the Locator ID Separation Protocol (LISP) feature of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload. This vulnerability is due to the incorrect handling of LISP packets. An attacker could exploit this vulnerability by sending a crafted LISP packet to an affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a denial of service (DoS) condition. Note: This vulnerability could be exploited over either IPv4 or IPv6 transport.

A remote attacker might be able to cause infinite recursion in PowerDNS Recursor 4.8.0 via a DNS query that retrieves DS records for a misconfigured domain, because QName minimization is used in QM fallback mode. This is fixed in 4.8.1.

uBlock Origin before 1.36.2 and nMatrix before 4.4.9 support an arbitrary depth of parameter nesting for strict blocking, which allows crafted web sites to cause a denial of service (unbounded recursion that can trigger memory consumption and a loss of all blocking functionality).

HTTP2ToRawGRPCServerCodec in gRPC Swift 1.1.1 and earlier allows remote attackers to deny service via the delivery of many small messages within a single HTTP/2 frame, leading to Uncontrolled Recursion and stack consumption.

IBM i 7.6, 7.5, 7.4, and 7.3 s vulnerable to a denial-of-service attack due to uncontrolled recursion in the Integrated Language Environment (ILE) compiler. An authenticated attacker could exploit this vulnerability by compiling specially crafted source code containing a specific combination of statements.

Incorrect packet validation allowed unbounded recursion parsing SCTP chunk parameters. This can eventually result in a stack overflow and panic. Remote attackers can craft packets which cause affected systems to panic. This affects any system where pf is configured to process traffic, independent of the configured ruleset.

Uncontrolled recursion in PostgreSQL SSL and GSS negotiation allows an attacker able to connect to a PostgreSQL AF_UNIX socket to achieve sustained denial of service. If SSL and GSS are both disabled, an attacker can do the same via access to a PostgreSQL TCP socket. Versions before PostgreSQL 18.4, 17.10, 16.14, 15.18, and 14.23 are affected.

In Moodle, the file repository's URL parsing required additional recursion handling to mitigate the risk of recursion denial of service.

The xmlStringGetNodeList function in tree.c in libxml2 2.9.3 and earlier, when used in recovery mode, allows context-dependent attackers to cause a denial of service (infinite recursion, stack consumption, and application crash) via a crafted XML document.

A flaw was discovered in GNU libiberty within demangle_path() in rust-demangle.c, as distributed in GNU Binutils version 2.36. A crafted symbol can cause stack memory to be exhausted leading to a crash.

jQuery 3.0.0-rc.1 is vulnerable to Denial of Service (DoS) due to removing a logic that lowercased attribute names. Any attribute getter using a mixed-cased name for boolean attributes goes into an infinite recursion, exceeding the stack call limit.

Net::DNS before 0.60, a Perl module, allows remote attackers to cause a denial of service (stack consumption) via a malformed compressed DNS packet with self-referencing pointers, which triggers an infinite loop.

Net::BitTorrent versions through 2.0.1 for Perl allow remote memory exhaustion via deeply nested bencoded input. bdecode recurses once per nested list or dictionary level with no depth cap, and each recursive call receives the remaining buffer by value while the list and dictionary branches capture the whole remainder, so every live recursion frame keeps its own copy of the shrinking buffer (O(N^2) bytes for an N-deep input). The decoder runs on every untrusted bencode source: .torrent files, BEP09 metadata fetched from peers, DHT messages, and tracker responses. A bencoded input of roughly 150,000 nested lists (about 150 KB on the wire) drives multi-gigabyte peak memory, so one short message from any peer, or one crafted .torrent file or magnet link, terminates the client.

The Zend Engine in PHP 4.x before 4.4.7, and 5.x before 5.2.2, allows remote attackers to cause a denial of service (stack exhaustion and PHP crash) via deeply nested arrays, which trigger deep recursion in the variable destruction routines.

msgpackr is a fast MessagePack NodeJS/JavaScript implementation. Prior to 1.10.1, when decoding user supplied MessagePack messages, users can trigger stuck threads by crafting messages that keep the decoder stuck in a loop. The fix is available in v1.10.1. Exploits seem to require structured cloning, replacing the 0x70 extension with your own (that throws an error or does something other than recursive referencing) should mitigate the issue.

Oniguruma before 6.9.3 allows Stack Exhaustion in regcomp.c because of recursion in regparse.c.

An issue was discovered in OSSEC 3.6.0. An uncontrolled recursion vulnerability in os_xml.c occurs when a large number of opening and closing XML tags is used. Because recursion is used in _ReadElem without restriction, an attacker can trigger a segmentation fault once unmapped memory is reached.

OPC Foundation UA .NET Standard versions prior to 1.4.365.48 and OPC UA .NET Legacy are vulnerable to an uncontrolled recursion, which may allow an attacker to trigger a stack overflow.

Squid is a caching proxy for the Web. Due to an Uncontrolled Recursion bug in versions 2.6 through 2.7.STABLE9, versions 3.1 through 5.9, and versions 6.0.1 through 6.5, Squid may be vulnerable to a Denial of Service attack against HTTP Request parsing. This problem allows a remote client to perform Denial of Service attack by sending a large X-Forwarded-For header when the follow_x_forwarded_for feature is configured. This bug is fixed by Squid version 6.6. In addition, patches addressing this problem for the stable releases can be found in Squid's patch archives.

In some circumstances, when DNSdist is configured to allow an unlimited number of queries on a single, incoming TCP connection from a client, an attacker can cause a denial of service by crafting a TCP exchange that triggers an exhaustion of the stack and a crash of DNSdist, causing a denial of service. The remedy is: upgrade to the patched 1.9.10 version. A workaround is to restrict the maximum number of queries on incoming TCP connections to a safe value, like 50, via the setMaxTCPQueriesPerConnection setting. We would like to thank Renaud Allard for bringing this issue to our attention.

Remarshal prior to v0.17.1 expands YAML alias nodes unlimitedly, hence Remarshal is vulnerable to Billion Laughs Attack. Processing untrusted YAML files may cause a denial-of-service (DoS) condition.

In Elasticsearch versions before 7.13.3 and 6.8.17 an uncontrolled recursion vulnerability that could lead to a denial of service attack was identified in the Elasticsearch Grok parser. A user with the ability to submit arbitrary queries to Elasticsearch could create a malicious Grok query that will crash the Elasticsearch node.

CBOR dissector crash in Wireshark 4.0.0 to 4.0.6 allows denial of service via packet injection or crafted capture file

TYPO3 is an open source PHP based web content management system. In TYPO3 before versions 9.5.25, 10.4.14, 11.1.1 requesting invalid or non-existing resources via HTTP triggers the page error handler which again could retrieve content to be shown as error message from another page. This leads to a scenario in which the application is calling itself recursively - amplifying the impact of the initial attack until the limits of the web server are exceeded. This is fixed in versions 9.5.25, 10.4.14, 11.1.1.

FreeSWITCH is a Software Defined Telecom Stack enabling the digital transformation from proprietary telecom switches to a software implementation that runs on any commodity hardware. Prior to version 1.11.1, a single unauthenticated WebSocket frame containing a deeply nested JSON document crashes the FreeSWITCH process via stack overflow, terminating all calls and sessions on the host. The recursion drives the worker thread's stack pointer into the stack guard page, raising SIGSEGV from the kernel before any usable write primitive develops. This issue has been patched in version 1.11.1.

Net::CIDR::Set versions through 0.20 for Perl did not validate IP addresses. The add method called the _encode method to parse addresses. If the addresses did not look like netmasks or network ranges, then they were assumed to single IP addresses and passed back to itself as a 32-bit or 128-bit netmask. If the argument was not a well-formed IP address, then this would lead to indefinite recursion. An attacker could use this to cause a denial of service.

The OpenAPI.NET SDK contains a useful object model for OpenAPI documents in .NET along with common serializers to extract raw OpenAPI JSON and YAML documents from the model. From 2.0.0-preview11 until 2.7.5 and 3.5.4, a small OpenAPI document containing a circular schema reference can cause process termination through stack overflow in Microsoft.OpenApi. The issue affects OpenAPI document parsing through public OpenAPI.NET reader APIs and has been confirmed across both JSON and YAML reader paths. This vulnerability is fixed in 2.7.5 and 3.5.4.

IBM Qiskit SDK 0.43.0 through 2.5.0 could allow an attacker to trigger a segmentation fault leading to a denial of service due to uncontrolled recursion in the parser.

MessagePack for C# is a MessagePack serializer for C#. Prior to 2.5.301 and 3.1.7, runtime-generated union deserializers emitted by DynamicUnionResolver do not call MessagePackSecurity.DepthStep(ref reader) and do not decrement reader.Depth around recursive deserialization and skip paths. This means union deserialization does not consistently participate in the maximum object graph depth enforcement that protects other recursive formatter paths. For unknown union keys, the emitted deserializer calls reader.Skip() on attacker-controlled data without an enclosing depth step. This vulnerability is fixed in 2.5.301 and 3.1.7.

MessagePack for C# is a MessagePack serializer for C#. Prior to 2.5.301 and 3.1.7, MessagePack-CSharp's JSON conversion helpers contain multiple recursion paths that do not consistently enforce a depth limit. These paths are in the JSON conversion component rather than normal typed MessagePack deserialization. MessagePackSerializer.ConvertFromJson recursively processes nested JSON arrays and objects in FromJsonCore() without consulting MessagePackSecurity.MaximumObjectGraphDepth. TinyJsonReader.ReadNextToken() recursively consumes comma and colon separator characters, allowing even malformed JSON with long separator runs to consume one stack frame per character. MessagePackSerializer.ConvertToJson applies depth checks to arrays and maps, but the typeless extension branch for ext-100 recursively calls ToJsonCore() without applying MessagePackSecurity.DepthStep(ref reader). Each path can allow attacker-controlled input to exhaust the process stack and trigger an uncatchable StackOverflowException instead of failing with a catchable parse or serialization exception. This vulnerability is fixed in 2.5.301 and 3.1.7.

MessagePack for C# is a MessagePack serializer for C#. Prior to 2.5.301 and 3.1.7, MessagePackReader.TrySkip() recursively descends into nested arrays and maps without incrementing the reader depth or calling the configured depth checks. This bypasses MessagePackSecurity.MaximumObjectGraphDepth, the library's documented protection against deeply nested object graphs. Many generated and dynamic formatters call reader.Skip() when they encounter unknown map keys, unknown array members, ignored fields, or data that should be skipped for forward compatibility. A deeply nested value in one of these skipped positions can therefore cause unbounded recursion and an uncatchable StackOverflowException. This vulnerability is fixed in 2.5.301 and 3.1.7.

protobufjs compiles protobuf definitions into JavaScript (JS) functions. Prior to 7.6.1 and 8.4.1, protobufjs could recurse without a depth limit while converting decoded messages to plain objects or JSON. This affected generated toObject() conversion and the custom google.protobuf.Any JSON conversion path. A crafted protobuf binary payload containing deeply nested Any values could cause the JavaScript call stack to be exhausted during conversion to JSON. This vulnerability is fixed in 7.6.1 and 8.4.1.

Uncontrolled Recursion vulnerability in Samsung Open Source Escargot allows Oversized Serialized Data Payloads. This issue affects Escargot: 590345cc6258317c5da850d846ce6baaf2afc2d3.

protobufjs compiles protobuf definitions into JavaScript (JS) functions. Prior to 7.5.6 and 8.0.2, protobufjs could recurse without a depth limit while decoding nested protobuf data. This affected both skipping unknown group fields and generated decoding of nested message fields. A crafted protobuf binary payload could cause the JavaScript call stack to be exhausted during decoding. This vulnerability is fixed in 7.5.6 and 8.0.2.

Billy is an interface filesystem abstraction for Go. Prior to versions 5.9.0 and 6.0.0-alpha.1, multiple components may improperly handle crafted or malformed input, resulting in panics, infinite loops, uncontrolled recursion, or excessive resource consumption. These issues arise from insufficient validation and missing safety mechanisms such as cycle detection, recursion limits, or defensive handling of unexpected states when processing untrusted repository data and filesystem structures. This issue has been patched in versions 5.9.0 and 6.0.0-alpha.1.

Symfony is a PHP framework for web and console applications and a set of reusable PHP components. Prior to 5.4.52, 6.4.40, 7.4.12, and 8.0.12, when the parser is exposed to attacker-controlled input, deeply nested mappings or sequences cause both the block-level (Parser::parseBlock()) and inline (Inline::parseSequence() / Inline::parseMapping()) parsers to recurse without a depth limit. A crafted document exhausts the PHP stack and crashes the worker. This issue is fixed in versions 5.4.52, 6.4.40, 7.4.12, and 8.0.12.

curl 7.21.0 to and including 7.73.0 is vulnerable to uncontrolled recursion due to a stack overflow issue in FTP wildcard match parsing.

An exploitable denial-of-service vulnerability exists in the resource record-parsing functionality of Videolabs libmicrodns 0.1.0. When parsing compressed labels in mDNS messages, the compression pointer is followed without checking for recursion, leading to a denial of service. An attacker can send an mDNS message to trigger this vulnerability.

A vulnerability in MongoDB Server's BSON validation logic allows an unauthenticated user to crash the mongod process by sending a specially crafted message. The BSON validator's handling of certain nested binary data structures permits uncontrolled mutual recursion between validation functions, where each re-entry resets internal depth tracking.