CVE-2026-0865 (GCVE-0-2026-0865)

Vulnerability from cvelistv5 – Published: 2026-01-20 21:26 – Updated: 2026-03-03 14:43
VLAI
Title
wsgiref.headers.Headers allows header newline injection
Summary
User-controlled header names and values containing newlines can allow injecting HTTP headers.
Severity
5.9 (Medium)
CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-74 - Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')
Assigner
PSF
References
Impacted products
Vendor Product Version
Python Software Foundation CPython Affected: 0 , < 3.10.20 (python)
Affected: 3.11.0 , < 3.11.15 (python)
Affected: 3.12.0 , < 3.12.13 (python)
Affected: 3.13.0 , < 3.13.12 (python)
Affected: 3.14.0 , < 3.14.3 (python)
Affected: 3.15.0a1 , < 3.15.0a6 (python)
Create a notification for this product.
Credits
Omar M. Hasan
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

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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.


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