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CVE-2026-12860 (GCVE-0-2026-12860)

Vulnerability from cvelistv5 – Published: 2026-08-03 02:55 – Updated: 2026-08-03 15:10
VLAI
Title
RSA PKCS#1 verification skips last two hash bytes in NULL-omitted path
Summary
In Bouncy Castle for Java before 1.85, RSA PKCS#1 verification skips last two hash bytes in NULL-omitted path. This issue also affects Bouncy Castle for Java LTS before 2.73.12.
Severity
8.7 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/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 15:09 UTC
CWE
  • CWE-347 - Improper Verification of Cryptographic Signature
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

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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.
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  • 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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