CVE-2026-1299

CVE Details

Release Date:	2026-01-23
Impact:	Moderate	What is this?

Description

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".

See more information about CVE-2026-1299 from MITRE CVE dictionary and NIST NVD

NOTE: The following CVSS metrics and score provided are preliminary and subject to review.

CVSS v3 metrics

Base Score:	7.1
Vector String:	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:N
Version:	3.1
Attack Vector:	Network
Attack Complexity:	Low
Privileges Required:	Low
User Interaction:	None
Scope:	Unchanged
Confidentiality Impact:	Low
Integrity Impact:	High
Availability Impact:	None

Errata information

Platform	Errata	Release Date
Oracle Linux version 8 (python3)	ELSA-2026-2128	2026-02-05