CVE-2026-1299 (GCVE-0-2026-1299)
Vulnerability from cvelistv5
Published
2026-01-23 16:27
Modified
2026-03-03 14:43
Severity ?
6.0 (Medium) - 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
CWE
Summary
The email module, specifically the "BytesGenerator" class, didn’t properly quote newlines for email headers when serializing an email message allowing for header injection when an email 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".
References
Impacted products
Vendor Product Version
Python Software Foundation CPython Version: 0
Version: 3.11.0
Version: 3.12.0
Version: 3.13.0
Version: 3.14.0
Version: 3.15.0a1
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