High 8.7Published Aug 3, 2026

CVE-2026-59639CMS verifySignatures returns true for SignedData with zero signers

Updated under an hour ago (2026-10-19 09:30 UTC)

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It affects Legion of the Bouncy Castle Inc. BC-JAVA and 5 other products. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

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Every CVE for Legion of the Bouncy Castle Inc. BC-JAVA

Exploited in the last 30 days

In Bouncy Castle for Java before 1.85, CMS verifySignatures returns true for SignedData with zero signers. 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).

CVSS: 8.7 HIGH (v4.0, CNA)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
Weakness (CWE): CWE-347
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: bcorg
NVD analysis: Analyzed
Record last updated: Aug 3, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

Legion of the Bouncy Castle Inc. BC-JAVA legion_of_the_bouncy_castle:bc_java (from the name)	before 1.85	CNA record
Legion of the Bouncy Castle Inc. BC-LTS-JAVA legion_of_the_bouncy_castle:bc_lts_java (from the name)	from 2.73.0 before 2.73.12	CNA record
Legion of the Bouncy Castle Inc. BC-FJA legion_of_the_bouncy_castle:bc_fja (from the name)	from 1.0.0 before 1.0.12; from 2.0.0 before 2.0.12; from 2.1.0 before 2.1.12	CNA record
bouncycastle bc-java bouncycastle:bc-java	before 1.85	NVD
bouncycastle bcpkix-fips bouncycastle:bcpkix-fips	before 1.0.12; from 2.0.7 before 2.0.12; from 2.1.8 before 2.1.12	NVD
bouncycastle bouncy_castle_for_java_lts bouncycastle:bouncy_castle_for_java_lts	through 2.73.11	NVD

References

https://github.com/bcgit/bc-java/wiki/CVE%E2%80%902026%E2%80%9059639vendor-advisory, third-party-advisory
https://github.com/bcgit/bc-java/commit/99ddc6dcc6782e6a76b0dd587c77e62eb7096ad0patch

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.