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CVE-2026-59651 (GCVE-0-2026-59651)

Vulnerability from cvelistv5 – Published: 2026-08-03 00:41 – Updated: 2026-08-03 13:31
VLAI
Title
BKS keystore accepts legacy version with 16-bit integrity MAC key
Summary
In Bouncy Castle for Java before 1.85, BKS keystore accepts legacy version with 16-bit integrity MAC key. This issue also affects Bouncy Castle for Java LTS before 2.73.12.
Severity
7.1 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/U:Amber
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-03 13:31 UTC
CWE
  • CWE-326 - Inadequate Encryption Strength
Assigner
References
Impacted products
Vendor Product Version CPE status
Legion of the Bouncy Castle Inc. BC-JAVA Affected: 0 , < 1.85 (maven)
guessed Create a notification for this product.
Legion of the Bouncy Castle Inc. BC-LTS-JAVA Affected: 2.73.0 , < 2.73.12 (maven)
guessed Create a notification for this product.
Credits
Alex Gaynor in collaboration with Claude and Anthropic Research
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.