CVE-2026-115877 (GCVE-0-2026-115877)

Vulnerability from cvelistv5 – Published: 2026-10-23 20:25 – Updated: 2026-10-29 14:23
VLAI
Title
Twisted: HTTP Request Smuggling in twisted.web via a Bare CR or LF in a Header Value
Summary
Twisted is an event-based framework for internet applications, supporting Python 3.6+. Prior to 26.10.0rc1, twisted.web.http.HTTPChannel.headerReceived rejects a NUL byte in an HTTP header value but accepts a bare carriage return or bare line feed. Because Twisted splits header lines only on CRLF, a hidden Content-Length header can remain folded into another value while a lenient front end treats the bare character as a line terminator. The resulting framing disagreement can smuggle a following request past front-end access controls, poison a shared connection or cache, and expose a later client to the wrong response. This issue is an incomplete-fix residual of earlier Twisted request-smuggling protections. This issue is fixed in version 26.10.0rc1.
Severity
5.4 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-10-29 14:21 UTC
CWE
  • CWE-444 - Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7913 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
twisted twisted Affected: < 26.10.0rc1
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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