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2 vulnerabilities found for libwebsockets by libwebsockets
CVE-2026-19773 (GCVE-0-2026-19773)
Vulnerability from nvd – Published: 2026-09-15 18:01 – Updated: 2026-09-16 03:57
VLAI
EPSS
VEX
Title
libwebsockets HTTP/2 HPACK Path Header Parsing Out-Of-Bounds Write Remote Code Execution Vulnerability
Summary
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.
Severity
9.8 (Critical)
SSVC
Exploitation: none
Automatable: yes
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-15 00:00 UTC
CWE
- CWE-787 - Out-of-bounds Write
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://www.zerodayinitiative.com/advisories/ZDI-… | x_research-advisory |
| https://github.com/warmcat/libwebsockets/commit/8… | vendor-advisory |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| libwebsockets | libwebsockets |
Affected:
b4b5aed3903eaff09cd76a410f69bbe5dff66f8e
|
Date Public
2026-08-24 21:16
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CVE-2026-19773 (GCVE-0-2026-19773)
Vulnerability from cvelistv5 – Published: 2026-09-15 18:01 – Updated: 2026-09-16 03:57
VLAI
EPSS
VEX
Title
libwebsockets HTTP/2 HPACK Path Header Parsing Out-Of-Bounds Write Remote Code Execution Vulnerability
Summary
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.
Severity
9.8 (Critical)
SSVC
Exploitation: none
Automatable: yes
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-15 00:00 UTC
CWE
- CWE-787 - Out-of-bounds Write
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://www.zerodayinitiative.com/advisories/ZDI-… | x_research-advisory |
| https://github.com/warmcat/libwebsockets/commit/8… | vendor-advisory |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| libwebsockets | libwebsockets |
Affected:
b4b5aed3903eaff09cd76a410f69bbe5dff66f8e
|
Date Public
2026-08-24 21:16
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