CVE-2026-3644: Vulnerability in Python Software Foundation CPython
The fix for CVE-2026-0672, which rejected control characters in http.cookies.Morsel, was incomplete. The Morsel.update(), |= operator, and unpickling paths were not patched, allowing control characters to bypass input validation. Additionally, BaseCookie.js_output() lacked the output validation applied to BaseCookie.output().
CVE-2026-3644: Vulnerability in Python Software Foundation CPython
Description
The fix for CVE-2026-0672, which rejected control characters in http.cookies.Morsel, was incomplete. The Morsel.update(), |= operator, and unpickling paths were not patched, allowing control characters to bypass input validation. Additionally, BaseCookie.js_output() lacked the output validation applied to BaseCookie.output().
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- PSF
- Date Reserved
- 2026-03-06T16:13:09.289Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 69b84a02771bdb174918694f
Added to database: 3/16/2026, 6:20:50 PM
Last updated: 3/16/2026, 6:21:31 PM
Views: 1
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