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Fencer Vulns
high 7.5

CVE-2026-59639 json

CMS verifySignatures returns true for SignedData with zero signers

published 2026-08-03 3 mo ago modified 2026-08-28 2 mo ago also EUVD-2026-52035

cvss
7.5
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 15%
public exploits
0
none known

Summary

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).

Patch / fix

  • Legion of the Bouncy Castle Inc. BC-JAVA 1.85
  • Legion of the Bouncy Castle Inc. BC-LTS-JAVA 2.73.12
  • Legion of the Bouncy Castle Inc. BC-FJA 1.0.12, 2.0.12, 2.1.12
  • bouncycastle Debian 14 1.86-1

debian advisories DEBIAN-CVE-2026-59639

  • bouncycastle SLES for SAP 15 SP6, SLES for SAP 15 SP5, SLES for SAP 15 SP4 +8 more 1.85-150200.3.38.1
  • bouncycastle SLES 16.0, SLES for SAP applications 16.0 1.85-160000.1.1

suse advisories SUSE-SU-2026:3559-1SUSE-SU-2026:23127-1SUSE-SU-2026:23150-1

  • bouncycastle openSUSE Leap 16.0 1.85-160000.1.1
  • bouncycastle openSUSE Tumbleweed 1.85-1.1

opensuse advisories openSUSE-SU-2026:21538-1openSUSE-SU-2026:11445-1

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-59639 updated cvss 7.5

org.bouncycastle/bcpkix-jdk15on: org.bouncycastle/bcpkix-fips: Bouncy Castle for Java: Cryptographic signature bypass

  • Red Hat AMQ Broker 7 bcprov-jdk18on Red Hat build of Apache Camel for Spring Boot 4 bcpkix-jdk18on, bcprov-jdk18on Red Hat build of Apicurio Registry 3 bcprov-lts8on
    affected: workaround, no fix available
  • Red Hat Ceph Storage 9 ceph, cephadm, librbd1, librgw2, rbd-nbd, ceph-mib, +19 more
    affected: workaround, no fix available “Fix deferred”
  • Red Hat JBoss Enterprise Application Platform 7 bcpg-jdk15on, bcpg-jdk18on, bcmail-jdk15on, bcmail-jdk18on, bcpkix-jdk18on, bcprov-jdk15on, +5 more
    affected: workaround, no fix planned “Will not fix”
  • Red Hat JBoss Enterprise Application Platform 8 bcpg-jdk18on, bcpkix-jdk18on, bcprov-jdk18on, bcjmail-jdk18on
    affected: workaround, no fix available
  • Red Hat Single Sign-On 7 bcpg-jdk18on, bcmail-jdk18on, bcpkix-jdk18on, bcprov-jdk18on, bcpkix-jdk15on 1.70
    affected: workaround, no fix available, no fix planned “Will not fix”
  • Red Hat AMQ Broker 7 bcpkix-jdk18on Red Hat build of Apache Camel 4 for Quarkus 3 bcpg-jdk18on, bcpkix-jdk18on, bcprov-jdk18on
    not affected: vulnerable code not present
  • Red Hat Build of Keycloak bcpkix-jdk18on, bcprov-jdk18on, rhbk/keycloak-rhel9
    not affected: vulnerable code cannot be controlled by adversary
  • Red Hat build of Quarkus bcpkix-jdk18on, bcprov-jdk18on Red Hat Enterprise Linux 8 resteasy, resteasy-javadoc Red Hat Enterprise Linux 9 resteasy, pki-resteasy-core, pki-resteasy-client, pki-resteasy-jackson2-provider, pki-resteasy-servlet-initializer Red Hat Fuse 7 bcpg-jdk15on, bcpg-jdk18on, bctls-jdk18on, bcmail-jdk15on, bcmail-jdk18on, bcpkix-jdk18on, +6 more
    not affected: vulnerable code not present
show 1 more
  • Red Hat JBoss Enterprise Application Platform Expansion Pack bcpg-jdk18on, bcpkix-jdk18on, bcprov-jdk18on, bcjmail-jdk18on
    not affected: component not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
yes
Technical impact
partial
Assessed
3 mo ago

Exploit prediction

0.24% chance of exploitation in the next 30 days, higher than 15% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 4.0 8.7 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
CNA 4.0 8.7 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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:Amber
NVD 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

Affected products

  • Legion of the Bouncy Castle Inc. BC-JAVA
  • Legion of the Bouncy Castle Inc. BC-LTS-JAVA
  • Legion of the Bouncy Castle Inc. BC-FJA

Classification

Weakness
  • CWE-347 Improper Verification of Cryptographic Signature

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.