{"cve":"CVE-2026-1299","nvd":{"published":"2026-01-23T17:16:12.977","modified":"2026-06-17T10:15:28.543","status":"Deferred","description":"The \nemail module, specifically the \"BytesGenerator\" class, didn’t properly quote newlines for email headers when \nserializing an email message allowing for header injection when an email\n is serialized. This is only applicable if using \"LiteralHeader\" writing headers that don't respect email folding rules, the new behavior will reject the incorrectly folded headers in \"BytesGenerator\".","cvss_v4":{"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N","score":6.0},"cvss_v3":null,"cwes":["CWE-93"],"references":["https://cve.org/CVERecord?id=CVE-2024-6923","https://github.com/python/cpython/commit/052e55e7d44718fe46cbba0ca995cb8fcc359413","https://github.com/python/cpython/commit/0a925ab591c45d6638f37b5e57796f36fa0e56d8","https://github.com/python/cpython/commit/7877fe424415bc4a13045e62a90a7277413d8cb9","https://github.com/python/cpython/commit/842ce19a0c0b58d61591e8f6a708c38db1fb94e4"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:21:16.563232421+00:00"},"epss":{"cve":"CVE-2026-1299","score":0.00573,"percentile":0.47375,"date":"2026-11-01"},"kev":null,"osv":[],"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."]}