Medium severity · published Apr 10, 2026
CVE-2026-1502
HTTP client proxy tunnel headers not validated for CR/LF
5.7
CVSS
0.6%
EPSS
No
On KEV
Description
CR/LF bytes were not rejected by HTTP client proxy tunnel headers or host.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.6% · higher than 47% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CP
CPython · Python Software Foundation
before 3.10.21; 3.11.0 before 3.11.16; 3.12.0 before 3.12.14; 3.13.0 before 3.13.14; 3.14.0a1 before 3.14.5rc1; 3.15.0a1 before 3.15.0b1 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-1502
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-1502
github.com
https://github.com/python/cpython/commit/05ed7ce7ae9e17c23a04085b2539fe6d6d3cef69
github.com
https://github.com/python/cpython/commit/56b7100b04e44ea27989242b176beb8f016b2c53
github.com
https://github.com/python/cpython/commit/58703ec1bdd1eb075e8b01a0c427683ce594dd3e
github.com
https://github.com/python/cpython/commit/9e071c9b28c17f347f81b388a003d4eeb3c7a8dd
github.com
https://github.com/python/cpython/commit/b1cf9016335cb637c5a425032e8274a224f4b2ed
github.com
https://github.com/python/cpython/commit/c00c386faa579ad71196d33408644478488e43ec
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