libcurl provides the `CURLOPT_CERTINFO` option to allow applications torequest details to be returned about a server's certificate chain.Due to an erroneous function, a malicious server could make libcurl built withNSS get stuck in a never-ending busy-loop when trying to retrieve thatinformation.

libcurl's ASN1 parser has this utf8asn1str() function used for parsing an ASN.1 UTF-8 string. Itcan detect an invalid field and return error. Unfortunately, when doing so it also invokes `free()` on a 4 byte localstack buffer. Most modern malloc implementations detect this error and immediately abort. Some however accept the input pointer and add that memory to its list of available chunks. This leads to the overwriting of nearby stack memory. The content of the overwrite is decided by the `free()` implementation; likely to be memory pointers and a set of flags. The most likely outcome of exploting this flaw is a crash, although it cannot be ruled out that more serious results can be had in special circumstances.

1. A cookie is set using the `secure` keyword for `https://target` 2. curl is redirected to or otherwise made to speak with `http://target` (same hostname, but using clear text HTTP) using the same cookie set 3. The same cookie name is set - but with just a slash as path (`path=\"/\",`). Since this site is not secure, the cookie *should* just be ignored. 4. A bug in the path comparison logic makes curl read outside a heap buffer boundary The bug either causes a crash or it potentially makes the comparison come to the wrong conclusion and lets the clear-text site override the contents of the secure cookie, contrary to expectations and depending on the memory contents immediately following the single-byte allocation that holds the path. The presumed and correct behavior would be to plainly ignore the second set of the cookie since it was already set as secure on a secure host so overriding it on an insecure host should not be okay.

Due to a mistake in libcurl's WebSocket code, a malicious server can send a particularly crafted packet which makes libcurl get trapped in an endless busy-loop. There is no other way for the application to escape or exit this loop other than killing the thread/process. This might be used to DoS libcurl-using application.

libcurl-using applications can ask for a specific client certificate to be used in a transfer. This is done with the `CURLOPT_SSLCERT` option (`--cert` with the command line tool).When libcurl is built to use the macOS native TLS library Secure Transport, an application can ask for the client certificate by name or with a file name - using the same option. If the name exists as a file, it will be used instead of by name.If the appliction runs with a current working directory that is writable by other users (like `/tmp`), a malicious user can create a file name with the same name as the app wants to use by name, and thereby trick the application to use the file based cert instead of the one referred to by name making libcurl send the wrong client certificate in the TLS connection handshake.

When curl retrieves an HTTP response, it stores the incoming headers so that they can be accessed later via the libcurl headers API. However, curl did not have a limit in how many or how large headers it would accept in a response, allowing a malicious server to stream an endless series of headers and eventually cause curl to run out of heap memory.

libcurl versions from 7.36.0 to before 7.64.0 is vulnerable to a heap buffer out-of-bounds read. The function handling incoming NTLM type-2 messages (`lib/vauth/ntlm.c:ntlm_decode_type2_target`) does not validate incoming data correctly and is subject to an integer overflow vulnerability. Using that overflow, a malicious or broken NTLM server could trick libcurl to accept a bad length + offset combination that would lead to a buffer read out-of-bounds.

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.

A use after free vulnerability exists in curl <7.87.0. Curl can be asked to *tunnel* virtually all protocols it supports through an HTTP proxy. HTTP proxies can (and often do) deny such tunnel operations. When getting denied to tunnel the specific protocols SMB or TELNET, curl would use a heap-allocated struct after it had been freed, in its transfer shutdown code path.

A use after free vulnerability exists in curl <v8.1.0 in the way libcurl offers a feature to verify an SSH server's public key using a SHA 256 hash. When this check fails, libcurl would free the memory for the fingerprint before it returns an error message containing the (now freed) hash. This flaw risks inserting sensitive heap-based data into the error message that might be shown to users or otherwise get leaked and revealed.

The function `read_data()` in security.c in curl before version 7.51.0 is vulnerable to memory double free.

A flaw was found in curl before version 7.51.0. The way curl handles cookies permits other threads to trigger a use-after-free leading to information disclosure.

The libcurl API function called `curl_maprintf()` before version 7.51.0 can be tricked into doing a double-free due to an unsafe `size_t` multiplication, on systems using 32 bit `size_t` variables.

Use-after-free vulnerability in libcurl before 7.50.1 allows attackers to control which connection is used or possibly have unspecified other impact via unknown vectors.

curl 7.75.0 through 7.76.1 suffers from a use-after-free vulnerability resulting in already freed memory being used when a TLS 1.3 session ticket arrives over a connection. A malicious server can use this in rare unfortunate circumstances to potentially reach remote code execution in the client. When libcurl at run-time sets up support for TLS 1.3 session tickets on a connection using OpenSSL, it stores pointers to the transfer in-memory object for later retrieval when a session ticket arrives. If the connection is used by multiple transfers (like with a reused HTTP/1.1 connection or multiplexed HTTP/2 connection) that first transfer object might be freed before the new session is established on that connection and then the function will access a memory buffer that might be freed. When using that memory, libcurl might even call a function pointer in the object, making it possible for a remote code execution if the server could somehow manage to get crafted memory content into the correct place in memory.

Due to use of a dangling pointer, libcurl 7.29.0 through 7.71.1 can use the wrong connection when sending data.

A heap use-after-free flaw was found in curl versions from 7.59.0 through 7.61.1 in the code related to closing an easy handle. When closing and cleaning up an 'easy' handle in the `Curl_close()` function, the library code first frees a struct (without nulling the pointer) and might then subsequently erroneously write to a struct field within that already freed struct.

If an attacker loaded a font using <code>FontFace()</code> on a background worker, a use-after-free could have occurred, leading to a potentially exploitable crash. This vulnerability affects Firefox < 107.

The Display Service module has a UAF vulnerability. Successful exploitation of this vulnerability may affect the display service availability.

Use-after-free in the JavaScript Engine component. This vulnerability was fixed in Firefox 150, Firefox ESR 115.35, Firefox ESR 140.10, Thunderbird 150, and Thunderbird 140.10.

The graphics display module has a UAF vulnerability when traversing graphic layers. Successful exploitation of this vulnerability may affect system availability.

Use-after-free in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 150, Firefox ESR 115.35, Firefox ESR 140.10, Thunderbird 150, and Thunderbird 140.10.

In libexpat through 2.4.9, there is a use-after free caused by overeager destruction of a shared DTD in XML_ExternalEntityParserCreate in out-of-memory situations.

A vulnerability has been identified in SIMATIC CP 1242-7 V2 (6GK7242-7KX31-0XE0) (All versions < V3.4.29), SIMATIC CP 1243-1 (6GK7243-1BX30-0XE0) (All versions < V3.4.29), SIMATIC CP 1243-1 DNP3 (incl. SIPLUS variants) (All versions < V3.4.29), SIMATIC CP 1243-1 IEC (incl. SIPLUS variants) (All versions < V3.4.29), SIMATIC CP 1243-7 LTE EU (6GK7243-7KX30-0XE0) (All versions < V3.4.29), SIMATIC CP 1243-7 LTE US (6GK7243-7SX30-0XE0) (All versions < V3.4.29), SIMATIC CP 1243-8 IRC (6GK7243-8RX30-0XE0) (All versions < V3.4.29), SIMATIC CP 1542SP-1 (6GK7542-6UX00-0XE0) (All versions < V2.3), SIMATIC CP 1542SP-1 IRC (6GK7542-6VX00-0XE0) (All versions < V2.3), SIMATIC CP 1543SP-1 (6GK7543-6WX00-0XE0) (All versions < V2.3), SIMATIC CP 443-1 (6GK7443-1EX30-0XE0) (All versions < V3.3), SIMATIC CP 443-1 (6GK7443-1EX30-0XE1) (All versions < V3.3), SIMATIC CP 443-1 Advanced (6GK7443-1GX30-0XE0) (All versions < V3.3), SIPLUS ET 200SP CP 1542SP-1 IRC TX RAIL (6AG2542-6VX00-4XE0) (All versions < V2.3), SIPLUS ET 200SP CP 1543SP-1 ISEC (6AG1543-6WX00-7XE0) (All versions < V2.3), SIPLUS ET 200SP CP 1543SP-1 ISEC TX RAIL (6AG2543-6WX00-4XE0) (All versions < V2.3), SIPLUS NET CP 1242-7 V2 (6AG1242-7KX31-7XE0) (All versions < V3.4.29), SIPLUS NET CP 443-1 (6AG1443-1EX30-4XE0) (All versions < V3.3), SIPLUS NET CP 443-1 Advanced (6AG1443-1GX30-4XE0) (All versions < V3.3), SIPLUS S7-1200 CP 1243-1 (6AG1243-1BX30-2AX0) (All versions < V3.4.29), SIPLUS S7-1200 CP 1243-1 RAIL (6AG2243-1BX30-1XE0) (All versions < V3.4.29), SIPLUS TIM 1531 IRC (6AG1543-1MX00-7XE0) (All versions < V2.3.6), TIM 1531 IRC (6GK7543-1MX00-0XE0) (All versions < V2.3.6). The webserver of the affected products contains a vulnerability that may lead to a denial of service condition. An attacker may cause a denial of service situation which leads to a restart of the webserver of the affected product.

A use-after-free vulnerability was found in __nfs42_ssc_open() in fs/nfs/nfs4file.c in the Linux kernel. This flaw allows an attacker to conduct a remote denial

Use-after-free in the Widget: Cocoa component. This vulnerability was fixed in Firefox 150, Firefox ESR 140.10, Thunderbird 150, and Thunderbird 140.10.

Use-after-free in the WebRTC component. This vulnerability was fixed in Firefox 150, Firefox ESR 140.10, Thunderbird 150, and Thunderbird 140.10.

It was possible to cause a use-after-free in the content process side of a WebTransport connection, leading to a potentially exploitable crash. This vulnerability was fixed in Firefox 136, Firefox ESR 115.21, Firefox ESR 128.8, Thunderbird 136, and Thunderbird 128.8.

SDP protocol dissector crash in Wireshark 4.6.0 to 4.6.4 allows denial of service

An issue was discovered in Softing OPC UA C++ SDK 5.66 through 6.x before 6.10. An OPC/UA browse request exceeding the server limit on continuation points may cause a use-after-free error

ehttp 1.0.6 before 17405b9 has an epoll_socket.cpp read_func use-after-free. An attacker can make many connections over a short time to trigger this.

Squid is a caching proxy for the Web. Prior to version 7.5, due to premature release of resource during expected lifetime and heap Use-After-Free bugs, Squid is vulnerable to Denial of Service when handling ICP traffic. This problem allows a remote attacker to perform a reliable and repeatable Denial of Service attack against the Squid service using ICP protocol. This attack is limited to Squid deployments that explicitly enable ICP support (i.e. configure non-zero `icp_port`). This problem _cannot_ be mitigated by denying ICP queries using `icp_access` rules. This bug is fixed in Squid version 7.5.

A vulnerability was found in Exim and classified as problematic. This issue affects some unknown processing of the component Regex Handler. The manipulation leads to use after free. The name of the patch is 4e9ed49f8f12eb331b29bd5b6dc3693c520fddc2. It is recommended to apply a patch to fix this issue. The identifier VDB-211073 was assigned to this vulnerability.

Use-after-free in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox 150 and Thunderbird 150.

Software installed and run as a non-privileged user may conduct improper GPU system calls to trigger use-after-free kernel exceptions.

PJSIP is a free and open source multimedia communication library written in C. Prior to version 2.17, a heap use-after-free vulnerability exists in PJSIP's event subscription framework (evsub.c) that is triggered during presence unsubscription (SUBSCRIBE with Expires=0). This issue has been patched in version 2.17.

Envoy is a cloud-native high-performance proxy. In versions prior to 1.22.1 the OAuth filter would try to invoke the remaining filters in the chain after emitting a local response, which triggers an ASSERT() in newer versions and corrupts memory on earlier versions. continueDecoding() shouldn’t ever be called from filters after a local reply has been sent. Users are advised to upgrade. There are no known workarounds for this issue.

A flaw was found in libsoup, a library for handling HTTP requests. This vulnerability, known as a Use-After-Free, occurs in the HTTP/2 server implementation. A remote attacker can exploit this by sending specially crafted HTTP/2 requests that cause authentication failures. This can lead to the application attempting to access memory that has already been freed, potentially causing application instability or crashes, resulting in a Denial of Service (DoS).

MariaDB Server v10.6.3 and below was discovered to contain an use-after-free in the component my_wildcmp_8bit_impl at /strings/ctype-simple.c.

MariaDB Server v10.6.3 and below was discovered to contain an use-after-free in the component VDec::VDec at /sql/sql_type.cc.

MariaDB Server v10.6.3 and below was discovered to contain an use-after-free in the component Item_func_in::cleanup(), which is exploited via specially crafted SQL statements.

An attacker might be able to trigger a use-after-free by sending crafted DNS queries to a DNSdist using the DNSQuestion:getEDNSOptions method in custom Lua code. In some cases DNSQuestion:getEDNSOptions might refer to a version of the DNS packet that has been modified, thus triggering a use-after-free and potentially a crash resulting in denial of service.

MariaDB Server v10.6 and below was discovered to contain an use-after-free in the component my_strcasecmp_8bit, which is exploited via specially crafted SQL statements.

An issue was discovered in the libpulse-binding crate before 1.2.1 for Rust. get_context can cause a use-after-free.

A flaw was found in QEMU. If the QIOChannelWebsock object is freed while it is waiting to complete a handshake, a GSource is leaked. This can lead to the callback firing later on and triggering a use-after-free in the use of the channel. This can be abused by a malicious client with network access to the VNC WebSocket port to cause a denial of service during the WebSocket handshake prior to the VNC client authentication.

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.23.0, the fix for the heap-use-after-free described in CVE-2026-24680 is incomplete. While the vulnerable execution flow referenced in the advisory exists in the SDL2 implementation, the fix appears to have been applied only to the SDL3 code path. In the SDL2 implementation, the pointer is not nulled after free. This creates a situation where the advisory suggests the vulnerability is fully resolved, while builds or environments still using SDL2 may retain the vulnerable logic. A complete fix is available in version 3.23.0.

The iaware module has a Use-After-Free (UAF) vulnerability. Successful exploitation of this vulnerability may affect the system functions.

Squid is a caching proxy for the Web. Prior to version 7.5, due to heap Use-After-Free, Squid is vulnerable to Denial of Service when handling ICP traffic. This problem allows a remote attacker to perform a reliable and repeatable Denial of Service attack against the Squid service using ICP protocol. This attack is limited to Squid deployments that explicitly enable ICP support (i.e. configure non-zero `icp_port`). This problem _cannot_ be mitigated by denying ICP queries using `icp_access` rules. Version 7.5 contains a patch.

A Use After Free vulnerability in the Advanced Forwarding Toolkit (AFT) manager process (aftmand) of Juniper Networks Junos OS allows an unauthenticated networked attacker to cause a kernel crash due to intensive polling of Abstracted Fabric (AF) interface statistics and thereby a Denial of Service (DoS). Continued gathering of AF interface statistics will create a sustained Denial of Service (DoS) condition. This issue affects Juniper Networks Junos OS on MX Series: 20.1 versions later than 20.1R1; 20.2 versions prior to 20.2R3-S5; 20.3 versions prior to 20.3R3-S4; 20.4 versions prior to 20.4R3; 21.1 versions prior to 21.1R2; 21.2 versions prior to 21.2R2.