CVE-2026-78161

A vulnerability was found in warmcat libwebsockets 4.5.0. Impacted is the function report_raw_cbor of the file lib/misc/lecp.c of the component LECP CBOR Recording. The manipulation results in out-of-bounds write. The attack can be launched remotely. The exploit has been made public and could be used. The patch is identified as 1d44554a1bb262db63ff4e240152a9deecd99054. It is best practice to apply a patch to resolve this issue.

Libwebsockets (LWS) is a flexible, lightweight pure C library for implementing modern network protocols easily with a tiny footprint, using a nonblocking event loop.

Security Fix(es):

libwebsockets HTTP/2 HPACK Path Header Parsing Out-Of-Bounds Write Remote Code Execution Vulnerability. This vulnerability allows remote attackers to execute arbitrary code on affected installations of libwebsockets. Authentication is not required to exploit this vulnerability.

The specific flaw exists within the parsing of HTTP/2 HPACK path header. The issue results from the lack of proper validation of user-supplied data, which can result in a write past the end of an allocated buffer. An attacker can leverage this vulnerability to execute code in the context of the current process. Was ZDI-CAN-31036.(CVE-2026-19773)

A vulnerability classified as critical was found in warmcat libwebsockets 4.5.0. The vulnerability is in the function report_raw_cbor in lib/misc/lecp.c when handling LECP CBOR recordings. This issue allows an out-of-bounds write (CWE-787), which could affect confidentiality, integrity, and availability. A proof-of-concept exploit is available.(CVE-2026-78161)

A vulnerability was found in warmcat libwebsockets 4.5.0. Impacted is the function report_raw_cbor of the file lib/misc/lecp.c of the component LECP CBOR Recording. The manipulation results in out-of-bounds write. The attack can be launched remotely. The exploit has been made public and could be used. The patch is identified as 1d44554a1bb262db63ff4e240152a9deecd99054. It is best practice to apply a patch to resolve this issue.

It was discovered that Libwebsockets incorrectly handled certain SSH protocol messages in its SSH protocol handler. A remote attacker could possibly use this issue to cause Libwebsockets to consume excessive resources, resulting in a denial of service. (CVE-2026-10650)

It was discovered that Libwebsockets incorrectly handled certain malformed CBOR data. A remote attacker could possibly use this issue to cause Libwebsockets to crash, resulting in a denial of service, or execute arbitrary code. This issue only affected Ubuntu 24.04 LTS and Ubuntu 26.04 LTS. (CVE-2026-78161)