A flaw was found in libsoup. A remote attacker could exploit an unsigned to signed conversion error in the `soup_body_input_stream_read_chunked()` function by sending a malicious HTTP request. This vulnerability occurs when libsoup operates behind a non-libsoup proxy server or as a proxy in front of a non-libsoup backend server. Successful exploitation can allow an attacker to bypass security controls, poison web caches, or gain unauthorized access.

The remote Ubuntu 16.04 LTS / 18.04 LTS / 20.04 LTS / 22.04 LTS / 24.04 LTS host has packages installed that are affected by multiple vulnerabilities as referenced in the USN-8890-1 advisory.

    It was discovered that libsoup incorrectly handled certain HTTP/2 requests. A remote attacker could     possibly use this issue to cause a denial of service. This issue only affected Ubuntu 24.04 LTS and Ubuntu     26.04 LTS. (CVE-2026-4271)

    It was discovered that libsoup incorrectly handled certain HTTPS proxy connections. A remote attacker     could possibly use this issue to obtain sensitive information. This issue only affected Ubuntu 22.04 LTS,     Ubuntu 24.04 LTS, and Ubuntu 26.04 LTS. (CVE-2026-5119)

    It was discovered that libsoup incorrectly parsed certain chunked HTTP requests. A remote attacker could     possibly use this issue to bypass security controls. This issue only affected Ubuntu 22.04 LTS, Ubuntu     24.04 LTS, and Ubuntu 26.04 LTS. (CVE-2026-6324)

    It was discovered that libsoup incorrectly handled proxy authentication credentials. A remote attacker     could possibly use this issue to obtain sensitive information. (CVE-2026-66339)

    It was discovered that libsoup incorrectly handled certain HTTP Range headers. A remote attacker could     possibly use this issue to cause a denial of service. (CVE-2026-77014, CVE-2026-77680)

    It was discovered that libsoup incorrectly handled certain HTTP/2 connections. A remote attacker could     possibly use this issue to obtain sensitive information or execute arbitrary code. This issue only     affected Ubuntu 22.04 LTS, Ubuntu 24.04 LTS, and Ubuntu 26.04 LTS. (CVE-2026-85197)

    It was discovered that libsoup incorrectly handled certain HTTP/2 transfers. A remote attacker could     possibly use this issue to cause a denial of service. This issue only affected Ubuntu 22.04 LTS, Ubuntu     24.04 LTS, and Ubuntu 26.04 LTS. (CVE-2026-85534)

Tenable has extracted the preceding description block directly from the Ubuntu security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

There are packages installed that are affected by a vulnerability referenced in the following CVE:

  - A flaw was found in libsoup. A remote attacker could exploit an unsigned to signed conversion error in the
    `soup_body_input_stream_read_chunked()` function by sending a malicious HTTP request. This vulnerability
    occurs when libsoup operates behind a non-libsoup proxy server or as a proxy in front of a non-libsoup
    backend server. Successful exploitation can allow an attacker to bypass security controls, poison web
    caches, or gain unauthorized access. (CVE-2026-6324)

According to the versions of the libsoup packages installed, the EulerOS installation on the remote host is affected by the following vulnerabilities :

    A flaw was found in libsoup. A remote attacker could exploit an unsigned to signed conversion error in the     `soup_body_input_stream_read_chunked()` function by sending a malicious HTTP request. This vulnerability     occurs when libsoup operates behind a non-libsoup proxy server or as a proxy in front of a non-libsoup     backend server. Successful exploitation can allow an attacker to bypass security controls, poison web     caches, or gain unauthorized access.(CVE-2026-6324)

Tenable has extracted the preceding description block directly from the EulerOS libsoup security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

According to the versions of the libsoup packages installed, the EulerOS installation on the remote host is affected by the following vulnerabilities :

    A flaw was found in SoupServer. This HTTP request smuggling vulnerability occurs because SoupServer     improperly handles requests that combine Transfer-Encoding: chunked and Connection: keep-alive headers. A     remote, unauthenticated client can exploit this by sending specially crafted requests, causing SoupServer     to fail to close the connection as required by RFC 9112. This allows the attacker to smuggle additional     requests over the persistent connection, leading to unintended request processing and potential denial-of-     service (DoS) conditions.(CVE-2026-1760)

    A flaw was found in libsoup. A remote attacker could exploit an unsigned to signed conversion error in the     `soup_body_input_stream_read_chunked()` function by sending a malicious HTTP request. This vulnerability     occurs when libsoup operates behind a non-libsoup proxy server or as a proxy in front of a non-libsoup     backend server. Successful exploitation can allow an attacker to bypass security controls, poison web     caches, or gain unauthorized access.(CVE-2026-6324)

    A flaw was found in libsoup's WebSocket implementation when using the permessage-deflate extension. The     extension's decompression loop (inflate()) processes data in chunks without enforcing an upper boundary     limit on the output buffer size. While libsoup limits the incoming compressed frame size via     max_incoming_payload_size, it fails to track or limit memory allocation during decompression. A separate     check for decompressed size (max_total_message_size) exists but executes only after inflation is complete,     and it is entirely disabled by default for client connections. A remote, unauthenticated attacker can     exploit this by sending a small, highly compressed payload (a decompression bomb), causing unbounded     memory allocation that triggers an Out-of-Memory (OOM) crash and a Denial of Service     (DoS).(CVE-2026-15709)

Tenable has extracted the preceding description block directly from the EulerOS libsoup security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote NewStart CGSL host, running version MAIN 7.02, has libsoup packages installed that are affected by multiple vulnerabilities:

  - 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. (CVE-2026-2369)

  - GNOME libsoup before 3.6.0 allows HTTP request smuggling in some configurations because '\0' characters at     the end of header names are ignored, i.e., a Transfer-Encoding\0: chunked header is treated the same as     a Transfer-Encoding: chunked header. (CVE-2024-52530)

  - 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.
    (CVE-2025-11021)

  - 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. The package is vulnerable to a heap buffer over-read when sniffing content     via the skip_insight_whitespace() function. Libsoup clients may read one byte out-of-bounds in response to     a crafted HTTP response by an HTTP server. (CVE-2025-2784)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

According to the versions of the libsoup packages installed, the EulerOS installation on the remote host is affected by the following vulnerabilities :

    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.(CVE-2026-5119)

    A flaw was found in libsoup. A remote attacker could exploit an unsigned to signed conversion error in the     `soup_body_input_stream_read_chunked()` function by sending a malicious HTTP request. This vulnerability     occurs when libsoup operates behind a non-libsoup proxy server or as a proxy in front of a non-libsoup     backend server. Successful exploitation can allow an attacker to bypass security controls, poison web     caches, or gain unauthorized access.(CVE-2026-6324)

    A flaw was found in SoupServer. This HTTP request smuggling vulnerability occurs because SoupServer     improperly handles requests that combine Transfer-Encoding: chunked and Connection: keep-alive headers. A     remote, unauthenticated client can exploit this by sending specially crafted requests, causing SoupServer     to fail to close the connection as required by RFC 9112. This allows the attacker to smuggle additional     requests over the persistent connection, leading to unintended request processing and potential denial-of-     service (DoS) conditions.(CVE-2026-1760)

Tenable has extracted the preceding description block directly from the EulerOS libsoup security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

According to the versions of the libsoup packages installed, the EulerOS installation on the remote host is affected by the following vulnerabilities :

    A flaw was found in libsoup. A remote attacker could exploit an unsigned to signed conversion error in the     `soup_body_input_stream_read_chunked()` function by sending a malicious HTTP request. This vulnerability     occurs when libsoup operates behind a non-libsoup proxy server or as a proxy in front of a non-libsoup     backend server. Successful exploitation can allow an attacker to bypass security controls, poison web     caches, or gain unauthorized access.(CVE-2026-6324)

    A flaw was found in SoupServer. This HTTP request smuggling vulnerability occurs because SoupServer     improperly handles requests that combine Transfer-Encoding: chunked and Connection: keep-alive headers. A     remote, unauthenticated client can exploit this by sending specially crafted requests, causing SoupServer     to fail to close the connection as required by RFC 9112. This allows the attacker to smuggle additional     requests over the persistent connection, leading to unintended request processing and potential denial-of-     service (DoS) conditions.(CVE-2026-1760)

Tenable has extracted the preceding description block directly from the EulerOS libsoup security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - A flaw was found in libsoup. A remote attacker could exploit an unsigned to signed conversion error in the     `soup_body_input_stream_read_chunked()` function by sending a malicious HTTP request. This vulnerability     occurs when libsoup operates behind a non-libsoup proxy server or as a proxy in front of a non-libsoup     backend server. Successful exploitation can allow an attacker to bypass security controls, poison web     caches, or gain unauthorized access. (CVE-2026-6324)

Note that Nessus relies on the presence of the package as reported by the vendor.

ID	Name	Product	Family	Type	Severity
363740	Ubuntu 16.04 LTS / 18.04 LTS / 20.04 LTS / 22.04 LTS / 24.04 LTS : libsoup vulnerabilities (USN-8890-1)	Nessus	Ubuntu Local Security Checks	Local	high
459945	Echo: libsoup3: security update to 3.6.6-1+e4	Tenable Cloud Security	Echo Local Security Checks	Local	medium
459945	Echo: libsoup3: security update to 3.6.6-1+e4	Tenable Self-Hosted Container Security	Echo Local Security Checks	Local	medium
347074	EulerOS 2.0 SP15 : libsoup (EulerOS-SA-2026-3785)	Nessus	Huawei Local Security Checks	Local	medium
346767	EulerOS 2.0 SP15 : libsoup (EulerOS-SA-2026-3810)	Nessus	Huawei Local Security Checks	Local	medium
343693	EulerOS 2.0 SP12 : libsoup (EulerOS-SA-2026-3353)	Nessus	Huawei Local Security Checks	Local	medium
343635	EulerOS 2.0 SP12 : libsoup (EulerOS-SA-2026-3278)	Nessus	Huawei Local Security Checks	Local	medium
343555	NewStart CGSL MAIN 7.02 : libsoup Multiple Vulnerabilities (NS-SA-2026-0100)	Nessus	NewStart CGSL Local Security Checks	Local	high
333427	EulerOS 2.0 SP11 : libsoup (EulerOS-SA-2026-3134)	Nessus	Huawei Local Security Checks	Local	high
333396	EulerOS 2.0 SP11 : libsoup (EulerOS-SA-2026-3079)	Nessus	Huawei Local Security Checks	Local	high
332925	EulerOS 2.0 SP13 : libsoup (EulerOS-SA-2026-2977)	Nessus	Huawei Local Security Checks	Local	medium
332904	EulerOS 2.0 SP13 : libsoup (EulerOS-SA-2026-3027)	Nessus	Huawei Local Security Checks	Local	medium
317955	Linux Distros Unpatched Vulnerability : CVE-2026-6324	Nessus	Misc.	Local	medium

Detections

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CVE-2026-6324

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Tenable Plugins

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