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CVE-2025-1936 (GCVE-0-2025-1936)

Vulnerability from cvelistv5 – Published: 2025-03-04 13:31 – Updated: 2026-04-13 14:27
VLAI
Title
Adding %00 and a fake extension to a jar: URL changed the interpretation of the contents
Summary
jar: URLs retrieve local file content packaged in a ZIP archive. The null and everything after it was ignored when retrieving the content from the archive, but the fake extension after the null was used to determine the type of content. This could have been used to hide code in a web extension disguised as something else like an image. This vulnerability was fixed in Firefox 136, Firefox ESR 128.8, Thunderbird 136, and Thunderbird 128.8.
Severity
7.3 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2025-03-25 17:55 UTC
CWE
  • CWE-158 - Improper Neutralization of Null Byte or NUL Character
Assigner
References
Impacted products
Vendor Product Version CPE status
Mozilla Firefox Unaffected: 128.8 , ≤ 128.* (rpm)
Unaffected: 136 , ≤ * (rpm)
guessed Create a notification for this product.
Mozilla Thunderbird Unaffected: 128.8 , ≤ 128.* (rpm)
Unaffected: 136 , ≤ * (rpm)
guessed Create a notification for this product.
Credits
Surya Dev Singh
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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