CVE-2026-19773

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.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector : AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/warmcat/libwebsockets/commit/824151862f37bc72f46d9a3e01d5b9408d313a0b
https://www.zerodayinitiative.com/advisories/ZDI-26-590/

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-15 19:17

Updated : 2026-09-16 04:18

NVD link : CVE-2026-19773

Mitre link : CVE-2026-19773

CVE.ORG link : CVE-2026-19773

JSON object : View

Products Affected

No product.

CWE

CWE-787

Out-of-bounds Write

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