CVE-2026-5588 (GCVE-0-2026-5588)

Vulnerability from cvelistv5 – Published: 2026-04-15 09:06 – Updated: 2026-05-18 23:22
VLAI?
Title
PKIX draft CompositeVerifier accepts empty signature sequence as valid.
Summary
Use of a Broken or Risky Cryptographic Algorithm vulnerability in Legion of the Bouncy Castle Inc. BC-JAVA bcpkix on all (pkix modules), Legion of the Bouncy Castle Inc. BCPKIX-FIPS bcpkix on All (pkix modules), Legion of the Bouncy Castle Inc. BCPIX-LTS bcpkix on All (pkix modules). This vulnerability is associated with program files JcaContentVerifierProviderBuilder.Java, JcaContentVerfierProviderBuilder.Java. This issue affects BC-JAVA: from 1.67 before 1.80.2, from 1.81 before 1.81.1, from 1.82 before 1.84; BCPKIX-FIPS: from 2.0.6 before 2.0.11, from 2.1.7 before 2.1.11; BCPIX-LTS: from 2.73.7 before 2.73.11.
Severity ?
6.3 (Medium)
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/U:Amber
CWE
  • CWE-327 - Use of a Broken or Risky Cryptographic Algorithm
Assigner
References
Impacted products
Vendor Product Version
Legion of the Bouncy Castle Inc. BC-JAVA Affected: 1.67 , < 1.80.2 (maven)
Affected: 1.81 , < 1.81.1 (maven)
Affected: 1.82 , < 1.84 (maven)
Create a notification for this product.
Legion of the Bouncy Castle Inc. BCPKIX-FIPS Affected: 2.0.6 , < 2.0.11 (maven)
Affected: 2.1.7 , < 2.1.11 (maven)
Create a notification for this product.
Legion of the Bouncy Castle Inc. BCPIX-LTS Affected: 2.73.7 , < 2.73.11 (maven)
Create a notification for this product.
Credits
Nicholas Carlini using Claude, Anthropic
Show details on NVD website
To clipboard 

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Taxonomy of the tags.




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.