{"cve":"CVE-2026-115877","nvd":{"published":"2026-10-23T21:17:23.643","modified":"2026-10-23T21:17:23.643","status":"Received","description":"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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N","score":5.4},"cwes":["CWE-444"],"references":["https://github.com/twisted/twisted/commit/022b6f7feb5980166c71f54e2c0d8f4f21ff6e1a","https://github.com/twisted/twisted/commit/1616f702d36eda8990a5a5b22ad70fab140a7eb1","https://github.com/twisted/twisted/pull/12755","https://github.com/twisted/twisted/releases/tag/twisted-26.10.0rc1","https://github.com/twisted/twisted/security/advisories/GHSA-q7qq-6mhp-9rc4"],"products":[],"source":"nvd","synced_at":"2026-10-24T16:53:35.584907681+00:00"},"epss":{"cve":"CVE-2026-115877","score":0.00257,"percentile":0.17142,"date":"2026-10-25"},"kev":null,"osv":[{"id":"GHSA-q7qq-6mhp-9rc4","url":"https://osv.dev/vulnerability/GHSA-q7qq-6mhp-9rc4","summary":"Twisted: HTTP Request Smuggling in twisted.web via a Bare CR or LF in a Header Value","modified":"2026-10-23T21:00:05.299702082Z","packages":[{"ecosystem":"PyPI","name":"twisted","purl":"pkg:pypi/twisted","ranges":["<26.10.0rc1"],"fixed":["26.10.0rc1"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}