{"id":"CVE-2026-1299","details":"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\".","aliases":["BIT-libpython-2026-1299","BIT-python-2026-1299","BIT-python-min-2026-1299","PSF-2026-8"],"modified":"2026-05-19T06:44:23.498683732Z","published":"2026-01-23T17:16:12.977Z","related":["ALSA-2026:2128","ALSA-2026:4165","ALSA-2026:4168","ALSA-2026:4216","ALSA-2026:4463","ALSA-2026:4473","ALSA-2026:4713","CGA-pjgm-mfph-cxr6","SUSE-SU-2026:0642-1","SUSE-SU-2026:0873-1","SUSE-SU-2026:0884-1","SUSE-SU-2026:0891-1","SUSE-SU-2026:0897-1","SUSE-SU-2026:1062-1","SUSE-SU-2026:1090-1","SUSE-SU-2026:1107-1","SUSE-SU-2026:1117-1","SUSE-SU-2026:1349-1","SUSE-SU-2026:1354-1","SUSE-SU-2026:20543-1","SUSE-SU-2026:20581-1","SUSE-SU-2026:20951-1","SUSE-SU-2026:20956-1","SUSE-SU-2026:21104-1","SUSE-SU-2026:21178-1","openSUSE-SU-2026:10206-1","openSUSE-SU-2026:10222-1","openSUSE-SU-2026:10223-1","openSUSE-SU-2026:10398-1","openSUSE-SU-2026:10404-1","openSUSE-SU-2026:20254-1","openSUSE-SU-2026:20517-1"],"references":[{"type":"WEB","url":"https://cve.org/CVERecord?id=CVE-2024-6923"},{"type":"WEB","url":"https://mail.python.org/archives/list/security-announce@python.org/thread/6ZZULGALJTITEAGEXLDJE2C6FORDXPBT/"},{"type":"REPORT","url":"https://github.com/python/cpython/issues/144125"},{"type":"FIX","url":"https://github.com/python/cpython/commit/0a925ab591c45d6638f37b5e57796f36fa0e56d8"},{"type":"FIX","url":"https://github.com/python/cpython/commit/7877fe424415bc4a13045e62a90a7277413d8cb9"},{"type":"FIX","url":"https://github.com/python/cpython/commit/842ce19a0c0b58d61591e8f6a708c38db1fb94e4"},{"type":"FIX","url":"https://github.com/python/cpython/commit/8cdf6204f4ae821f32993f8fc6bad0d318f95f36"},{"type":"FIX","url":"https://github.com/python/cpython/commit/e417f05ad77a4c30ddc07f99e90fc0cef43e831a"},{"type":"FIX","url":"https://github.com/python/cpython/pull/144126"},{"type":"FIX","url":"https://github.com/python/cpython/commit/052e55e7d44718fe46cbba0ca995cb8fcc359413"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/python/cpython","events":[{"introduced":"0"},{"fixed":"052e55e7d44718fe46cbba0ca995cb8fcc359413"}]},{"type":"GIT","repo":"https://github.com/python/cpython","events":[{"introduced":"0"},{"fixed":"0a925ab591c45d6638f37b5e57796f36fa0e56d8"}]},{"type":"GIT","repo":"https://github.com/python/cpython","events":[{"introduced":"0"},{"fixed":"7877fe424415bc4a13045e62a90a7277413d8cb9"}]},{"type":"GIT","repo":"https://github.com/python/cpython","events":[{"introduced":"0"},{"fixed":"842ce19a0c0b58d61591e8f6a708c38db1fb94e4"}]},{"type":"GIT","repo":"https://github.com/python/cpython","events":[{"introduced":"0"},{"fixed":"8cdf6204f4ae821f32993f8fc6bad0d318f95f36"}]},{"type":"GIT","repo":"https://github.com/python/cpython","events":[{"introduced":"0"},{"fixed":"e417f05ad77a4c30ddc07f99e90fc0cef43e831a"}]}],"versions":["v0.9.8","v0.9.9","v1.0.1","v1.0.2","v1.1","v1.1.1","v1.2","v1.2b1","v1.2b2","v1.2b3","v1.2b4","v1.3","v1.3b1","v1.4","v1.4b1","v1.4b2","v1.4b3","v1.5","v1.5.1","v1.5.2","v1.5.2a1","v1.5.2a2","v1.5.2b1","v1.5.2b2","v1.5.2c1","v1.5a1","v1.5a2","v1.5a3","v1.5a4","v1.5b1","v1.5b2","v1.6a1","v1.6a2","v2.0","v2.0b1","v2.0b2","v2.0c1","v2.1","v2.1a1","v2.1a2","v2.1b1","v2.1b2","v2.1c1","v2.1c2","v2.2a3","v2.3c1","v2.3c2","v2.4","v2.4a1","v2.4a2","v2.4a3","v2.4b1","v2.4b2","v2.4c1","v3.0a1","v3.0a2","v3.0a3","v3.0a4","v3.0a5","v3.0b1","v3.0b2","v3.0b3","v3.0rc1","v3.0rc2","v3.0rc3","v3.1","v3.10.0a1","v3.10.0a7","v3.10.0b1","v3.10.0b2","v3.10.0b3","v3.10.0b4","v3.10.0rc1","v3.10.0rc2","v3.10.1","v3.10.10","v3.10.11","v3.10.12","v3.10.13","v3.10.14","v3.10.15","v3.10.16","v3.10.17","v3.10.18","v3.10.19","v3.10.2","v3.10.3","v3.10.4","v3.10.5","v3.10.6","v3.10.7","v3.10.8","v3.10.9","v3.11.0a3","v3.11.0a4","v3.11.0a5","v3.11.0a6","v3.11.0a7","v3.11.0b1","v3.11.0b2","v3.11.0b3","v3.11.0b4","v3.11.0b5","v3.11.0rc1","v3.11.0rc2","v3.11.1","v3.11.10","v3.11.11","v3.11.12","v3.11.13","v3.11.14","v3.11.2","v3.11.3","v3.11.4","v3.11.5","v3.11.6","v3.11.7","v3.11.8","v3.11.9","v3.12.0","v3.12.0a1","v3.12.0a2","v3.12.0a3","v3.12.0a4","v3.12.0a5","v3.12.0a6","v3.12.0a7","v3.12.0b1","v3.12.0b2","v3.12.0b3","v3.12.0b4","v3.12.0rc1","v3.12.0rc2","v3.12.0rc3","v3.12.1","v3.12.10","v3.12.11","v3.12.12","v3.12.2","v3.12.3","v3.12.4","v3.12.5","v3.12.6","v3.12.7","v3.12.8","v3.12.9","v3.13.0","v3.13.0a1","v3.13.0a2","v3.13.0a3","v3.13.0a4","v3.13.0a5","v3.13.0a6","v3.13.0b1","v3.13.0b2","v3.13.0b3","v3.13.0b4","v3.13.0rc1","v3.13.0rc2","v3.13.0rc3","v3.13.1","v3.13.10","v3.13.11","v3.13.2","v3.13.3","v3.13.4","v3.13.5","v3.13.6","v3.13.7","v3.13.8","v3.14.0","v3.14.0a1","v3.14.0a2","v3.14.0a3","v3.14.0a4","v3.14.0a5","v3.14.0a6","v3.14.0a7","v3.14.0b1","v3.14.0b2","v3.14.0b3","v3.14.0b4","v3.14.0rc1","v3.14.0rc2","v3.14.0rc3","v3.14.1","v3.14.2","v3.15.0a1","v3.15.0a2","v3.15.0a3","v3.15.0a4","v3.15.0a5","v3.1a1","v3.1a2","v3.1b1","v3.1rc1","v3.1rc2","v3.2a1","v3.2a2","v3.2a3","v3.2a4","v3.2b1","v3.2b2","v3.2rc1","v3.2rc2","v3.2rc3","v3.3.0a2","v3.3.0a3","v3.3.0a4","v3.3.0b1","v3.3.0b2","v3.3.0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