CVE-2026-3644 (GCVE-0-2026-3644)

Vulnerability from cvelistv5 – Published: 2026-03-16 17:37 – Updated: 2026-04-07 22:01
VLAI
Title
Incomplete control character validation in http.cookies
Summary
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().
Severity
6 (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
  • CWE-20 - Improper Input Validation
  • CWE-116 - Improper Encoding or Escaping of Output
Assigner
PSF
References
Impacted products
Vendor Product Version
Python Software Foundation CPython Affected: 0 , < 3.13.13 (python)
Affected: 3.14.0 , < 3.14.4 (python)
Affected: 3.15.0a1 , < 3.15.0a8 (python)
Create a notification for this product.
Credits
Stan Ulbrych Stan Ulbrych Victor Stinner Seth Larson Vyom Yadav
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Detection rules are retrieved from Rulezet.