ZDI-26-590: libwebsockets HTTP/2 HPACK Path Header Parsing Out-Of-Bounds Write Remote Code Execution Vulnerability

Code

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No public source repository is identified for this product.

Timeline

Detection, updates, and resolution for this record.

1. Aug 24, 2026 · Catalog

   Detected

   This vulnerability allows remote attackers to execute arbitrary code on affected installations of libwebsockets. Authentication is not required to exploit this vulnerability. The ZDI has assigned a CVSS rating of 9.8. The following CVEs are assigned: CVE-2026-19773.

Sources

• CVE.orgVulnerability recordCVE-2026-19773

  Official CVE identifier

  cve.org
• FIRST EPSSExploitation probabilityCVE-2026-19773

  30-day exploitation probability 0.6%

  first.org
• Zero Day InitiativeCoordinated disclosureZDI-26-590

  This vulnerability allows remote attackers to execute arbitrary code on affected installations of libwebsockets. Authentication is not required to exploit this vulnerability. The ZDI has assigned a CVSS rating of 9.8. The following CVEs are assigned: CVE-2026-19773.

  zerodayinitiative.com