Ghostwire

CVE-2026-91920: A flaw was found in the ChunkReader component of the Undertow web server, which is used to handle chunked transfer...

MEDIUM CVSS 0.0 EPSS 0.24%

Published: October 30, 2026 | Last Modified: October 30, 2026

Description

A flaw was found in the ChunkReader component of the Undertow web server, which is used to handle chunked transfer encoding in HTTP requests. The issue occurs because a security check for the chunk size is performed before the value is shifted, allowing a specifically crafted 15-digit chunk size to bypass the limit and overflow into internal state flags. This can cause the server to terminate a request body prematurely and interpret the remaining data as a separate, smuggled request.

Ghostwire Analysis — What This Means Practically

Exploitation Probability (EPSS): Low — 0.24% (15th percentile)

Low exploitation probability based on current threat landscape data. Standard patching timeline is appropriate.

This analysis is generated by Ghostwire from NVD, CISA KEV, EPSS, and open-source intelligence data. Verify findings through primary sources before acting.

Security Coverage (1 articles)

References