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TI-2026-12671 Aliases CVE-2026-15055GHSA-mx98-27g8-c9xc

PKCS#8 / PBES2 decryptors honour unbounded KDF cost from input

Priority LOW 24CWE-770Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
Passive
Attack complexity
Low
Attack requirements
None
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · Low
Fix status
Partial Red Hat: 5 without a fix

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-770.

Summary

In Bouncy Castle for Java before 1.85, PKCS#8 / PBES2 decryptors honour unbounded KDF cost from input. This issue also affects Bouncy Castle for Java LTS before 2.73.12, and Bouncy Castle for Java FIPS (BC-FJA) before bcpkix-fips 1.0.12 (1.0.X series), 2.0.12 (2.0.X series) and 2.1.12 (2.1.X series).

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00339 27th percentileScored 2026-11-07
Fix Partial BC-JAVA (Legion of the Bouncy Castle Inc.): 1.85BC-LTS-JAVA (Legion of the Bouncy Castle Inc.): 2.73.12+1 more productRed Hat: 5 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
Legion of the Bouncy Castle Inc.BC-JAVAbefore 1.851.85Patch availableCNA
Legion of the Bouncy Castle Inc.BC-LTS-JAVA2.73.0 to before 2.73.122.73.12Patch availableCNA
Legion of the Bouncy Castle Inc.BC-FJA1.0.0 to before 1.0.12; 2.0.0 to before 2.0.12; 2.1.0 to before 2.1.121.0.12, 2.0.12, 2.1.12Patch availableCNA

CPE configurations NVD · 3

CPEVersionsRoleVendor
cpe:2.3:a:bouncycastle:bc-java:*:*:*:*:*:*:*:*before 1.85VulnerableLegion of the Bouncy Castle Inc.
cpe:2.3:a:bouncycastle:bcpkix-fips:*:*:*:*:*:*:*:*before 1.0.12; 2.0.7 to before 2.0.12; 2.1.8 to before 2.1.12VulnerableLegion of the Bouncy Castle Inc.
cpe:2.3:a:bouncycastle:bouncy_castle_for_java_lts:*:*:*:*:*:*:*:*up to 2.73.11VulnerableLegion of the Bouncy Castle Inc.

Remediation

  • Fix · CNA BC-JAVA (Legion of the Bouncy Castle Inc.) Fixed in 1.85
  • Fix · CNA BC-LTS-JAVA (Legion of the Bouncy Castle Inc.) Fixed in 2.73.12
  • Fix · CNA BC-FJA (Legion of the Bouncy Castle Inc.) Fixed in 1.0.12, 2.0.12, 2.1.12

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    Legion of the Bouncy Castle BC-JAVA 1.85

    32 records Highest priority Priority MEDIUM 23 MEDIUM, 9 LOW

    Other records, highest priority first

    • TI-2026-42545 MTI/A0 DH agreement exponentiates unvalidated peer valuePriority MEDIUM 48
    • TI-2026-42533 JSSE hostname verifier CN-fallback enabled by default despite documented opt-inPriority MEDIUM 48
    • TI-2026-41816 Stapled OCSP response accepted without binding to the checked certificatePriority MEDIUM 48
  • Release ·

    Legion of the Bouncy Castle BC-LTS-JAVA 2.73.12

    28 records Highest priority Priority MEDIUM 20 MEDIUM, 8 LOW

    Other records, highest priority first

    • TI-2026-42545 MTI/A0 DH agreement exponentiates unvalidated peer valuePriority MEDIUM 48
    • TI-2026-42533 JSSE hostname verifier CN-fallback enabled by default despite documented opt-inPriority MEDIUM 48
    • TI-2026-41816 Stapled OCSP response accepted without binding to the checked certificatePriority MEDIUM 48
Show 1 more group
  • Release ·

    Legion of the Bouncy Castle BC-FJA 1.0.12, 2.0.12, 2.1.12

    5 records Highest priority Priority MEDIUM 3 MEDIUM, 2 LOW

    Other records, highest priority first

    • TI-2026-42537 CMS AuthenticatedData content not bound to MAC when authAttrs presentPriority MEDIUM 43
    • TI-2026-42534 CMS verifySignatures returns true for SignedData with zero signersPriority MEDIUM 43
    • TI-2026-10940 CMS AuthEnvelopedData fails to enforce tag-length on decryptionPriority MEDIUM 43

Vendor assessments

Red Hat

Red Hat rating: Important. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat AMQ ClientsAffectedNo fix yet
Red Hat Ceph Storage 9AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux 9AffectedNo fix yet
Red Hat JBoss Enterprise Application Platform 7AffectedNo fix planned: Will not fix
Red Hat Single Sign-On 7AffectedNo fix planned: Will not fix
Not affected: 3 products
  • Red Hat Enterprise Linux 8
  • Red Hat Enterprise Linux 9
  • Red Hat Fuse 7

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-15055
  2. 2026-10-03 Alias added: GHSA-mx98-27g8-c9xc
  3. 2026-10-16 Affected versions changed · Red Hat
  4. 2026-10-20 Affected versions changed · Red Hat
  5. 2026-11-03 Affected versions changed · Red Hat

References

  • TI-2018-15967 Legion of the Bouncy Castle Legion of the Bouncy Castle Java Cryptography APIs 1.58 up to… CVSS 3.1CRITICAL 9.8
  • TI-2017-09736 BouncyCastle JCE TLS Bleichenbacher/ROBOT CVSS 3.0HIGH 7.5
  • TI-2026-42545 MTI/A0 DH agreement exponentiates unvalidated peer value CVSS 4.0CRITICAL 9.3
  • TI-2026-42533 JSSE hostname verifier CN-fallback enabled by default despite documented opt-in CVSS 4.0CRITICAL 9.3
  • TI-2026-41816 Stapled OCSP response accepted without binding to the checked certificate CVSS 4.0CRITICAL 9.3
  • TI-2026-07701 Name Constraints bypass via trailing dot in rfc822Name and URI CVSS 4.0CRITICAL 9.3
See all 52 →

Sources