CVE-2026-0719

libsoup is an HTTP client/server library for GNOME. It uses GObjects and the glib main loop, to integrate well with GNOME applications, and also has a synchronous API, for use in threaded applications.

Security Fix(es):

A flaw in libsoup’s HTTP header handling allows multiple Host: headers in a request and returns the last occurrence for server-side processing. Common front proxies often honor the first Host: header, so this mismatch can cause vhost confusion where a proxy routes a request to one backend but the backend interprets it as destined for another host. This discrepancy enables request-smuggling style attacks, cache poisoning, or bypassing host-based access controls when an attacker supplies duplicate Host headers.(CVE-2025-14523)

A flaw was found in libsoup's NTLM (NT LAN Manager) authentication module. When NTLM authentication is enabled, a local attacker can exploit a stack-based buffer overflow vulnerability in the md4sum() function. This allows the attacker to overwrite adjacent memory, which may result in arbitrary code execution with the privileges of the affected application.(CVE-2026-0719)

libsoup is an HTTP client/server library for GNOME. It uses GObjects and the glib main loop, to integrate well with GNOME applications, and also has a synchronous API, for use in threaded applications.

Security Fix(es):

A flaw in libsoup’s HTTP header handling allows multiple Host: headers in a request and returns the last occurrence for server-side processing. Common front proxies often honor the first Host: header, so this mismatch can cause vhost confusion where a proxy routes a request to one backend but the backend interprets it as destined for another host. This discrepancy enables request-smuggling style attacks, cache poisoning, or bypassing host-based access controls when an attacker supplies duplicate Host headers.(CVE-2025-14523)

A flaw was found in libsoup's NTLM (NT LAN Manager) authentication module. When NTLM authentication is enabled, a local attacker can exploit a stack-based buffer overflow vulnerability in the md4sum() function. This allows the attacker to overwrite adjacent memory, which may result in arbitrary code execution with the privileges of the affected application.(CVE-2026-0719)

libsoup is an HTTP client/server library for GNOME. It uses GObjects and the glib main loop, to integrate well with GNOME applications, and also has a synchronous API, for use in threaded applications.

Security Fix(es):

A flaw in libsoup’s HTTP header handling allows multiple Host: headers in a request and returns the last occurrence for server-side processing. Common front proxies often honor the first Host: header, so this mismatch can cause vhost confusion where a proxy routes a request to one backend but the backend interprets it as destined for another host. This discrepancy enables request-smuggling style attacks, cache poisoning, or bypassing host-based access controls when an attacker supplies duplicate Host headers.(CVE-2025-14523)

A flaw was found in libsoup's NTLM (NT LAN Manager) authentication module. When NTLM authentication is enabled, a local attacker can exploit a stack-based buffer overflow vulnerability in the md4sum() function. This allows the attacker to overwrite adjacent memory, which may result in arbitrary code execution with the privileges of the affected application.(CVE-2026-0719)

libsoup is an HTTP client/server library for GNOME. It uses GObjects and the glib main loop, to integrate well with GNOME applications, and also has a synchronous API, for use in threaded applications.

Security Fix(es):

A flaw in libsoup’s HTTP header handling allows multiple Host: headers in a request and returns the last occurrence for server-side processing. Common front proxies often honor the first Host: header, so this mismatch can cause vhost confusion where a proxy routes a request to one backend but the backend interprets it as destined for another host. This discrepancy enables request-smuggling style attacks, cache poisoning, or bypassing host-based access controls when an attacker supplies duplicate Host headers.(CVE-2025-14523)

A flaw was found in libsoup's NTLM (NT LAN Manager) authentication module. When NTLM authentication is enabled, a local attacker can exploit a stack-based buffer overflow vulnerability in the md4sum() function. This allows the attacker to overwrite adjacent memory, which may result in arbitrary code execution with the privileges of the affected application.(CVE-2026-0719)

libsoup is an HTTP client/server library for GNOME. It uses GObjects and the glib main loop, to integrate well with GNOME applications, and also has a synchronous API, for use in threaded applications.

Security Fix(es):

A flaw in libsoup’s HTTP header handling allows multiple Host: headers in a request and returns the last occurrence for server-side processing. Common front proxies often honor the first Host: header, so this mismatch can cause vhost confusion where a proxy routes a request to one backend but the backend interprets it as destined for another host. This discrepancy enables request-smuggling style attacks, cache poisoning, or bypassing host-based access controls when an attacker supplies duplicate Host headers.(CVE-2025-14523)

A flaw was found in libsoup’s WebSocket frame processing when handling incoming messages. If a non-default configuration is used where the maximum incoming payload size is unset, the library may read memory outside the intended bounds. This can cause unintended memory exposure or a crash. Applications using libsoup’s WebSocket support with this configuration may be impacted.(CVE-2026-0716)

A flaw was found in libsoup's NTLM (NT LAN Manager) authentication module. When NTLM authentication is enabled, a local attacker can exploit a stack-based buffer overflow vulnerability in the md4sum() function. This allows the attacker to overwrite adjacent memory, which may result in arbitrary code execution with the privileges of the affected application.(CVE-2026-0719)

A flaw was found in libsoup, an HTTP client library. This vulnerability, known as CRLF (Carriage Return Line Feed) Injection, occurs when an HTTP proxy is configured and the library improperly handles URL-decoded input used to create the Host header. A remote attacker can exploit this by providing a specially crafted URL containing CRLF sequences, allowing them to inject additional HTTP headers or complete HTTP request bodies. This can lead to unintended or unauthorized HTTP requests being forwarded by the proxy, potentially impacting downstream services.(CVE-2026-1467)

A flaw was found in the libsoup HTTP library that can cause proxy authentication credentials to be sent to unintended destinations. When handling HTTP redirects, libsoup removes the Authorization header but does not remove the Proxy-Authorization header if the request is redirected to a different host. As a result, sensitive proxy credentials may be leaked to third-party servers. Applications using libsoup for HTTP communication may unintentionally expose proxy authentication data.(CVE-2026-1539)

A flaw was found in libsoup. This stack-based buffer overflow vulnerability occurs during the parsing of multipart HTTP responses due to an incorrect length calculation. A remote attacker can exploit this by sending a specially crafted multipart HTTP response, which can lead to memory corruption. This issue may result in application crashes or arbitrary code execution in applications that process untrusted server responses, and it does not require authentication or user interaction.(CVE-2026-1761)

libsoup is an HTTP client/server library for GNOME. It uses GObjects and the glib main loop, to integrate well with GNOME applications, and also has a synchronous API, for use in threaded applications.

Security Fix(es):

A flaw in libsoup’s HTTP header handling allows multiple Host: headers in a request and returns the last occurrence for server-side processing. Common front proxies often honor the first Host: header, so this mismatch can cause vhost confusion where a proxy routes a request to one backend but the backend interprets it as destined for another host. This discrepancy enables request-smuggling style attacks, cache poisoning, or bypassing host-based access controls when an attacker supplies duplicate Host headers.(CVE-2025-14523)

A flaw was found in libsoup’s WebSocket frame processing when handling incoming messages. If a non-default configuration is used where the maximum incoming payload size is unset, the library may read memory outside the intended bounds. This can cause unintended memory exposure or a crash. Applications using libsoup’s WebSocket support with this configuration may be impacted.(CVE-2026-0716)

A flaw was found in libsoup's NTLM (NT LAN Manager) authentication module. When NTLM authentication is enabled, a local attacker can exploit a stack-based buffer overflow vulnerability in the md4sum() function. This allows the attacker to overwrite adjacent memory, which may result in arbitrary code execution with the privileges of the affected application.(CVE-2026-0719)

A flaw was found in libsoup, an HTTP client library. This vulnerability, known as CRLF (Carriage Return Line Feed) Injection, occurs when an HTTP proxy is configured and the library improperly handles URL-decoded input used to create the Host header. A remote attacker can exploit this by providing a specially crafted URL containing CRLF sequences, allowing them to inject additional HTTP headers or complete HTTP request bodies. This can lead to unintended or unauthorized HTTP requests being forwarded by the proxy, potentially impacting downstream services.(CVE-2026-1467)

A flaw was found in the libsoup HTTP library that can cause proxy authentication credentials to be sent to unintended destinations. When handling HTTP redirects, libsoup removes the Authorization header but does not remove the Proxy-Authorization header if the request is redirected to a different host. As a result, sensitive proxy credentials may be leaked to third-party servers. Applications using libsoup for HTTP communication may unintentionally expose proxy authentication data.(CVE-2026-1539)

A flaw was found in libsoup. This stack-based buffer overflow vulnerability occurs during the parsing of multipart HTTP responses due to an incorrect length calculation. A remote attacker can exploit this by sending a specially crafted multipart HTTP response, which can lead to memory corruption. This issue may result in application crashes or arbitrary code execution in applications that process untrusted server responses, and it does not require authentication or user interaction.(CVE-2026-1761)

Libsoup is an HTTP library implementation in C. It was originally part of a SOAP (Simple Object Access Protocol) implementation called Soup, but the SOAP and non-SOAP parts have now been split into separate packages.

Security Fix(es):

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).(CVE-2025-32908)

A flaw was identified in the NTLM authentication handling of the libsoup HTTP library, used by GNOME and other applications for network communication. When processing extremely long passwords, an internal size calculation can overflow due to improper use of signed integers. This results in incorrect memory allocation on the stack, followed by unsafe memory copying. As a result, applications using libsoup may crash unexpectedly, creating a denial-of-service risk.(CVE-2026-0719)

A flaw was found in libsoup. This stack-based buffer overflow vulnerability occurs during the parsing of multipart HTTP responses due to an incorrect length calculation. A remote attacker can exploit this by sending a specially crafted multipart HTTP response, which can lead to memory corruption. This issue may result in application crashes or arbitrary code execution in applications that process untrusted server responses, and it does not require authentication or user interaction.(CVE-2026-1761)

A flaw was found in libsoup, an HTTP client/server library. This HTTP Request Smuggling vulnerability arises from non-RFC-compliant parsing in the soup_filter_input_stream_read_line() logic, where libsoup accepts malformed chunk headers, such as lone line feed (LF) characters instead of the required carriage return and line feed (CRLF). A remote attacker can exploit this without authentication or user interaction by sending specially crafted chunked requests. This allows libsoup to parse and process multiple HTTP requests from a single network message, potentially leading to information disclosure.(CVE-2026-1801)

A flaw was identified in libsoup, a widely used HTTP library in GNOME-based systems. When processing specially crafted HTTP Range headers, the library may improperly validate requested byte ranges. In certain build configurations, this could allow a remote attacker to access portions of server memory beyond the intended response. Exploitation requires a vulnerable configuration and access to a server using the embedded SoupServer component.(CVE-2026-2443)

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).(CVE-2026-4271)

Libsoup is an HTTP library implementation in C. It was originally part of a SOAP (Simple Object Access Protocol) implementation called Soup, but the SOAP and non-SOAP parts have now been split into separate packages.

Security Fix(es):

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).(CVE-2025-32908)

A flaw was identified in the NTLM authentication handling of the libsoup HTTP library, used by GNOME and other applications for network communication. When processing extremely long passwords, an internal size calculation can overflow due to improper use of signed integers. This results in incorrect memory allocation on the stack, followed by unsafe memory copying. As a result, applications using libsoup may crash unexpectedly, creating a denial-of-service risk.(CVE-2026-0719)

A flaw was found in libsoup. This stack-based buffer overflow vulnerability occurs during the parsing of multipart HTTP responses due to an incorrect length calculation. A remote attacker can exploit this by sending a specially crafted multipart HTTP response, which can lead to memory corruption. This issue may result in application crashes or arbitrary code execution in applications that process untrusted server responses, and it does not require authentication or user interaction.(CVE-2026-1761)

A flaw was found in libsoup, an HTTP client/server library. This HTTP Request Smuggling vulnerability arises from non-RFC-compliant parsing in the soup_filter_input_stream_read_line() logic, where libsoup accepts malformed chunk headers, such as lone line feed (LF) characters instead of the required carriage return and line feed (CRLF). A remote attacker can exploit this without authentication or user interaction by sending specially crafted chunked requests. This allows libsoup to parse and process multiple HTTP requests from a single network message, potentially leading to information disclosure.(CVE-2026-1801)

A flaw was identified in libsoup, a widely used HTTP library in GNOME-based systems. When processing specially crafted HTTP Range headers, the library may improperly validate requested byte ranges. In certain build configurations, this could allow a remote attacker to access portions of server memory beyond the intended response. Exploitation requires a vulnerable configuration and access to a server using the embedded SoupServer component.(CVE-2026-2443)

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).(CVE-2026-4271)

Libsoup is an HTTP library implementation in C. It was originally part of a SOAP (Simple Object Access Protocol) implementation called Soup, but the SOAP and non-SOAP parts have now been split into separate packages. libsoup uses the Glib main loop and is designed to work well with GTK applications. This enables GNOME applications to access HTTP servers on the network in a completely asynchronous fashion, very similar to the Gtk+ programming model (a synchronous operation mode is also supported for those who want it), but the SOAP parts were removed long ago.

Security Fix(es):

• libsoup: Signed to Unsigned Conversion Error Leading to Stack-Based Buffer Overflow in libsoup NTLM Authentication (CVE-2026-0719)

• libsoup: Stack-Based Buffer Overflow in libsoup Multipart Response Parsingmultipart HTTP response (CVE-2026-1761)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Spice client MSI installers for Windows clients

Security Fix(es):

• libsoup: Signed to Unsigned Conversion Error Leading to Stack-Based Buffer Overflow in libsoup NTLM Authentication (CVE-2026-0719)

• libsoup: Stack-Based Buffer Overflow in libsoup Multipart Response Parsingmultipart HTTP response (CVE-2026-1761)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

The libsoup packages provide an HTTP client and server library for GNOME.

Security Fix(es):

• libsoup: Signed to Unsigned Conversion Error Leading to Stack-Based Buffer Overflow in libsoup NTLM Authentication (CVE-2026-0719)

• libsoup: Stack-Based Buffer Overflow in libsoup Multipart Response Parsingmultipart HTTP response (CVE-2026-1761)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

The libsoup packages provide an HTTP client and server library for GNOME.

Security Fix(es):

• libsoup: Signed to Unsigned Conversion Error Leading to Stack-Based Buffer Overflow in libsoup NTLM Authentication (CVE-2026-0719)

• libsoup: Stack-Based Buffer Overflow in libsoup Multipart Response Parsingmultipart HTTP response (CVE-2026-1761)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

A flaw was identified in the NTLM authentication handling of the libsoup HTTP library, used by GNOME and other applications for network communication. When processing extremely long passwords, an internal size calculation can overflow due to improper use of signed integers. This results in incorrect memory allocation on the stack, followed by unsafe memory copying. As a result, applications using libsoup may crash unexpectedly, creating a denial-of-service risk.

Libsoup is an HTTP library implementation in C. It was originally part of a SOAP (Simple Object Access Protocol) implementation called Soup, but the SOAP and non-SOAP parts have now been split into separate packages. libsoup uses the Glib main loop and is designed to work well with GTK applications. This enables GNOME applications to access HTTP servers on the network in a completely asynchronous fashion, very similar to the Gtk+ programming model (a synchronous operation mode is also supported for those who want it), but the SOAP parts were removed long ago.

Security Fix(es):

• libsoup: Signed to Unsigned Conversion Error Leading to Stack-Based Buffer Overflow in libsoup NTLM Authentication (CVE-2026-0719)
• libsoup: Stack-Based Buffer Overflow in libsoup Multipart Response Parsingmultipart HTTP response (CVE-2026-1761)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

The libsoup packages provide an HTTP client and server library for GNOME.

Security Fix(es):

• libsoup: Signed to Unsigned Conversion Error Leading to Stack-Based Buffer Overflow in libsoup NTLM Authentication (CVE-2026-0719)
• libsoup: Stack-Based Buffer Overflow in libsoup Multipart Response Parsingmultipart HTTP response (CVE-2026-1761)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

The libsoup packages provide an HTTP client and server library for GNOME.

Security Fix(es):

• libsoup: Signed to Unsigned Conversion Error Leading to Stack-Based Buffer Overflow in libsoup NTLM Authentication (CVE-2026-0719)
• libsoup: Stack-Based Buffer Overflow in libsoup Multipart Response Parsingmultipart HTTP response (CVE-2026-1761)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

• CVE-2026-0719 fix integer overflow in NTLM authentication when processing excessively long passwords

• CVE-2026-1761: fix stack-based buffer overflow in multipart HTTP response parsing caused by incorrect length calculation in soup_filter_input_stream_read_until()
• CVE-2026-0719: fix stack-based buffer overflow in NTLM authentication caused by integer overflow in md4sum() with excessively long passwords

• CVE-2026-1761: fix stack-based buffer overflow in multipart HTTP response parsing caused by incorrect length calculation in soup_filter_input_stream_read_until()
• CVE-2026-0719: fix stack-based buffer overflow in NTLM authentication caused by integer overflow in md4sum() with excessively long passwords

• CVE-2026-1761: fix stack-based buffer overflow in multipart HTTP response parsing caused by incorrect length calculation in soup_filter_input_stream_read_until()
• CVE-2026-0719: fix stack-based buffer overflow in NTLM authentication caused by integer overflow in md4sum() with excessively long passwords

• CVE-2026-1761: fix memory corruption when parsing multipart HTTP responses
• CVE-2026-0719: fix integer overflow in NTLM authentication when processing excessively long passwords
• added upstream tests for CVE-2024-52531, CVE-2025-32914, CVE-2025-4948
• merged CVE-2025-2784 and CVE-2025-32053
• modified added tests for CVE-2025-46421 as it used 3.x version API
• skip connection-test

These are all security issues fixed in the libsoup-3_0-0-3.6.5-11.1 package on the GA media of openSUSE Tumbleweed.

These are all security issues fixed in the libsoup-2_4-1-2.74.3-14.1 package on the GA media of openSUSE Tumbleweed.

This update for libsoup fixes the following issues:

• CVE-2025-11021: Fixed out-of-bounds read in Cookie Date Handling of libsoup HTTP Library (bsc#1250562).
• CVE-2026-0719: Fixed stack-based buffer overflow in NTLM authentication can lead to arbitrary code execution (bsc#1256399).
• CVE-2026-0716: Fixed improper bounds handling may allow out-of-bounds read (bsc#1256418).

This update for libsoup2 fixes the following issues:

• CVE-2025-4476: null pointer dereference may lead to denial of service (bsc#1243422).
• CVE-2025-14523: Duplicate Host Header Handling Causes Host-Parsing Discrepancy (bsc#1254876).
• CVE-2025-32049: Denial of Service attack to websocket server (bsc#1240751).
• CVE-2026-0716: improper bounds handling may allow out-of-bounds read (bsc#1256418).
• CVE-2026-0719: stack-based buffer overflow in NTLM authentication can lead to arbitrary code execution (bsc#1256399).
• CVE-2026-1467: lack of input sanitization can lead to unintended or unauthorized HTTP requests (bsc#1257398).
• CVE-2026-1539: proxy authentication credentials leaked via the Proxy-Authorization header when handling HTTP redirects (bsc#1257441).
• CVE-2026-1760: improper handling of HTTP requests combining certain headers by SoupServer can lead to HTTP request smuggling and potential DoS (bsc#1257597).
• CVE-2026-2369: Buffer overread due to integer underflow when handling zero-length resources (bsc#1258120).
• CVE-2026-2443: out-of-bounds read when processing specially crafted HTTP Range headers can lead to heap information disclosure to remote attackers (bsc#1258170).
• CVE-2026-2708: HTTP request smuggling via duplicate Content-Length headers (bsc#1258508).

Root has patched CVE-2026-0719 in the libsoup2.4 package for Root:Debian:12. Multiple fixed versions available.

Root has patched CVE-2026-0719 in the libsoup3 package for Root:Debian:13. Multiple fixed versions available.

This update for libsoup fixes the following issues:

• CVE-2025-14523: Reject duplicated Host in headers and followed upsteram update (bsc#1254876).
• CVE-2026-0719: Fixed overflow for password md4sum (bsc#1256399)

This update for libsoup fixes the following issues:

• CVE-2025-14523: Reject duplicated Host in headers and followed upstream update (bsc#1254876).
• CVE-2026-0716: Fixed out-of-bounds read for websocket (bsc#1256418)
• CVE-2026-0719: Fixed overflow for password md4sum (bsc#1256399)

This update for libsoup2 fixes the following issues:

• CVE-2025-14523: Reject duplicated Host in headers and followed upstream update (bsc#1254876).
• CVE-2026-0719: Fixed overflow for password md4sum (bsc#1256399)