HTTP client proxy tunnel headers not validated for CR/LF
13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 5.7epss 0.6%
exploitation probability
0.6%top 54% of all CVEs
observed exploitation
nono source reports it
CR/LF bytes were not rejected by HTTP client proxy tunnel headers or host.
CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:P/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N
Affected products
Python Software Foundation · CPythonReferences
https://github.com/python/cpython/commit/05ed7ce7ae9e17c23a04085b2539fe6d6d3cef69https://github.com/python/cpython/commit/56b7100b04e44ea27989242b176beb8f016b2c53https://github.com/python/cpython/commit/58703ec1bdd1eb075e8b01a0c427683ce594dd3ehttps://github.com/python/cpython/commit/9e071c9b28c17f347f81b388a003d4eeb3c7a8ddhttps://github.com/python/cpython/commit/b1cf9016335cb637c5a425032e8274a224f4b2edhttps://github.com/python/cpython/commit/c00c386faa579ad71196d33408644478488e43echttps://github.com/python/cpython/issues/146211https://github.com/python/cpython/pull/146212https://mail.python.org/archives/list/security-announce@python.org/thread/2IVPAEQWUJBCTQZEJEVTYCIKSMQPGRZ3/http://www.openwall.com/lists/oss-security/2026/04/11/4