Last updated 25 August 2025

Last updated 25 August 2025

A stack based buffer overflow vulnerability has been reported in GNOME libsoup 2.58. The flaw is caused due to a boundary error within the "soupfilterinputstreamreaduntil()" function when parsing chunk encoded HTTP traffic and affects both the server and client functionality of libsoup.

A remote attacker could exploit this flaw to cause a crash or, potentially, execute arbitrary code by sending a specially crafted HTTP request to a server using the libsoup HTTP server functionality or by tricking a user into connecting to a malicious HTTP server with an application using the libsoup HTTP client functionality.

Please note that the libsoup packages as shipped with Red Hat Enterprise Linux 7 contain a "stack smashing protection" mitigation for the relevant function, which makes exploitation significantly harder. Thus, in most cases an exploitation attempt should be mitigated to a mere crash. However, successful exploitation to execute arbitrary code can't be ruled out entirely.

A flaw was found in libsoup. An integer underflow vulnerability occurs when processing content with a zero-length resource, leading to a buffer overread. This can allow an attacker to potentially access sensitive information or cause an application level denial of service.

A use-after-free type vulnerability was found in libsoup, in the soupmessageheadersgetcontentdisposition() function. This flaw allows a malicious HTTP client to cause memory corruption in the libsoup server.

GNOME libsoup before 3.6.1 allows a buffer overflow in applications that perform conversion to UTF-8 in soupheaderparseparamliststrict.

A flaw was found in libsoup's SoupServer. A remote attacker could exploit a use-after-free vulnerability where the soupserverdisconnect() function frees connection objects prematurely, even if a TLS handshake is still pending. If the handshake completes after the connection object has been freed, a dangling pointer is accessed, leading to a server crash and a Denial of Service.

A flaw was found in libsoup. When establishing HTTPS tunnels through a configured HTTP proxy, sensitive session cookies are transmitted in cleartext within the initial HTTP CONNECT request. A network-positioned attacker or a malicious HTTP proxy can intercept these cookies, leading to potential session hijacking or user impersonation.

GNOME libsoup before 3.6.1 has an infinite loop and memory consumption. during the reading of certain patterns of WebSocket data from clients.

GNOME libsoup before 3.6.0 allows HTTP request smuggling in some configurations

A flaw was found in libsoup. The SoupWebsocketConnection may accept a large WebSocket message, which may cause libsoup to allocate memory and lead to a denial of service (DoS).

A flaw was found in libsoup, where the soupmessageheadersgetcontentdisposition() function is vulnerable to a NULL pointer dereference. This flaw allows a malicious HTTP peer to crash a libsoup client or server that uses this function.

A flaw was found in libsoup. The implementation of HTTP range requests is vulnerable to a resource consumption attack. This flaw allows a malicious client to request the same range many times in a single HTTP request, causing the server to use large amounts of memory. This does not allow for a full denial of service.

A flaw was found in libsoup. The HTTP/2 server in libsoup may not fully validate the values of pseudo-headers :scheme, :authority, and :path, which may allow a user to cause a denial of service (DoS).

A flaw was found in libsoup, where the soupheadersparserequest() function may be vulnerable to an out-of-bound read. This flaw allows a malicious user to use a specially crafted HTTP request to crash the HTTP server.

A flaw was found in the soupmultipartnewfrommessage() function of the libsoup HTTP library, which is commonly used by GNOME and other applications to handle web communications. The issue occurs when the library processes specially crafted multipart messages. Due to improper validation, an internal calculation can go wrong, leading to an integer underflow. This can cause the program to access invalid memory and crash. As a result, any application or server using libsoup could be forced to exit unexpectedly, creating a denial-of-service (DoS) risk.

A flaw was found in the cookie date handling logic of the libsoup HTTP library, widely used by GNOME and other applications for web communication. When processing cookies with specially crafted expiration dates, the library may perform an out-of-bounds memory read. This flaw could result in unintended disclosure of memory contents, potentially exposing sensitive information from the process using libsoup.

A flaw was found in the asynchronous message queue handling of the libsoup library, widely used by GNOME and WebKit-based applications to manage HTTP/2 communications. When network operations are aborted at specific timing intervals, an internal message queue item may be freed twice due to missing state synchronization. This leads to a use-after-free memory access, potentially crashing the affected application. Attackers could exploit this behavior remotely by triggering specific HTTP/2 read and cancel sequences, resulting in a denial-of-service condition.

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).

Vulnerability Reference:

A flaw in libsoup's WebSocket implementation allows a remote attacker to trigger a denial of service (DoS) by exploiting a protocol validation failure.

Component / Vulnerable Part:

libsoup -> libsoup/websocket/soup-websocket-connection.c (Control frame parser)

Technical Analysis & Root Cause:

Per RFC 6455 §5.5, WebSocket control frames (PING, PONG, CLOSE) must not exceed a payload length of 125 bytes and cannot be fragmented. libsoup's frame parsing logic fails to immediately reject non-compliant control frames exceeding this limit. When an oversized control frame is received, the unexpected state disrupts the state machine or triggers an unhandled execution error, forcing the library to abruptly crash.

Impact:

A remote, unauthenticated attacker (client or server) can send a single malformed, oversized control frame to instantly terminate the connection wrapper, resulting in a remote denial of service for any application using libsoup WebSockets.

A flaw was found in libsoup, where the soupmultipartnewfrommessage() function is vulnerable to an out-of-bounds read. This flaw allows a malicious HTTP client to induce the libsoup server to read out of bounds.

A flaw was found in Libsoup. The server-side digest authentication implementation in the SoupAuthDomainDigest class does not properly track issued nonces or enforce the required incrementing nonce-count (nc) attribute. This vulnerability allows a remote attacker to capture a single valid authentication header and replay it repeatedly. Consequently, the attacker can bypass authentication and gain unauthorized access to protected resources, impersonating the legitimate user.

A flaw was found in libsoup. The chunked transfer encoding parser uses a permissive parsing function for chunk sizes that silently accepts inputs violating RFC 9112, including leading whitespace, plus sign prefixes, and trailing invalid characters. When libsoup operates behind a strict frontend proxy, this parsing differential can be exploited to smuggle HTTP requests.

A flaw was found in libsoup. The package is vulnerable to a heap buffer over-read when sniffing content via the skipinsightwhitespace() function. Libsoup clients may read one byte out-of-bounds in response to a crafted HTTP response by an HTTP server.

Out-of-Bounds Read vulnerability in the cookie date handling code of the libsoup HTTP library. The flaw is caused by improper bounds checking in the soupdatetimetostring() function when formatting crafted cookie expiration dates. An attacker can exploit this by sending specially crafted HTTP cookies, potentially leading to unintended memory disclosure. In production builds, the impact is expected to be limited to incorrect output rather than consistent crashes.

A flaw was found in libsoup. When libsoup clients encounter an HTTP redirect, they mistakenly send the HTTP Authorization header to the new host that the redirection points to. This allows the new host to impersonate the user to the original host that issued the redirect.

A flaw was found in libsoup. A vulnerability in the sniffunknown() function may lead to heap buffer over-read.

A flaw was found in libsoup. A vulnerability in snifffeedorhtml() and skipinsignificantspace() functions may lead to a heap buffer over-read.

A flaw was found in libsoup, where soupauthdigestauthenticate() is vulnerable to a NULL pointer dereference. This issue may cause the libsoup client to crash.

A flaw was found in libsoup, where SoupAuthDigest is vulnerable to a NULL pointer dereference. The HTTP server may cause the libsoup client to crash.