CVE-2026-59650
published 2026-08-03CVE-2026-59650: In Bouncy Castle for Java before 1.85, MTI/A0 DH agreement exponentiates unvalidated peer value. This issue also affects Bouncy Castle for Java LTS before…
PriorityP349critical9.3CVSS 4.0
AVNACLATNPRNUINVCHVIHVANSCNSINSANEXCRXIRXARXMAVXMACXMATXMPRXMUIXMVCXMVIXMVAXMSCXMSIXMSAXSXAUXRXVXREXUAmber
EPSS
0.28%
19.7th percentile
In Bouncy Castle for Java before 1.85, MTI/A0 DH agreement exponentiates unvalidated peer value. This issue also affects Bouncy Castle for Java LTS before 2.73.12.
Affected
2 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| legion_of_the_bouncy_castle_inc | bc-java | < 1.85 | 1.85 |
| legion_of_the_bouncy_castle_inc | bc-lts-java | >= 2.73.0 < 2.73.12 | 2.73.12 |
CVSS provenance
nvdv4.09.3CRITICALCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/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
vendor_redhat9.3CRITICAL
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VulDB
Legion of the Bouncy Castle up to 1.84/2.73.11 input validation
vuldb·2026-08-03·CVSS 9.3
CVE-2026-59650 [CRITICAL] Legion of the Bouncy Castle up to 1.84/2.73.11 input validation
A vulnerability was found in Legion of the Bouncy Castle Bouncy Castle up to 1.84/2.73.11 and classified as critical. This impacts an unknown function. Executing a manipulation can lead to improper input validation.
This vulnerability appears as CVE-2026-59650. The attack may be performed from remote. There is no available exploit.
It is suggested to upgrade the affected component.
GHSA
In Bouncy Castle for Java before 1.85, MTI/A0 DH agreement exponentiates unvalidated peer value.
ghsa_unreviewed·2026-08-03
CVE-2026-59650 [CRITICAL] CWE-20 In Bouncy Castle for Java before 1.85, MTI/A0 DH agreement exponentiates unvalidated peer value.
In Bouncy Castle for Java before 1.85, MTI/A0 DH agreement exponentiates unvalidated peer value. This issue also affects Bouncy Castle for Java LTS before 2.73.12.
Red Hat
bouncycastle: Bouncy Castle for Java: Cryptographic key compromise due to unvalidated Diffie-Hellman peer value
vendor_redhat·2026-08-03·CVSS 9.3
CVE-2026-59650 [CRITICAL] CWE-325 bouncycastle: Bouncy Castle for Java: Cryptographic key compromise due to unvalidated Diffie-Hellman peer value
bouncycastle: Bouncy Castle for Java: Cryptographic key compromise due to unvalidated Diffie-Hellman peer value
In Bouncy Castle for Java before 1.85, MTI/A0 DH agreement exponentiates unvalidated peer value. This issue also affects Bouncy Castle for Java LTS before 2.73.12.
A flaw was found in Bouncy Castle for Java. The software fails to validate Diffie-Hellman peer values during key agreement. A remote attacker can exploit this flaw to compromise cryptographic keys, potentially leading to the decryption of sensitive communications or successful impersonation.
Statement: This is an Important vulnerability where Bouncy Castle for Java, as used in Red Hat products, fails to validate Diffie-Hellman peer values during key agreement. This flaw allows a remote attacker to compromise cryptog
No detection rules found.
No public exploits indexed.
Bugzilla
CVE-2026-59650 bouncycastle: Bouncy Castle for Java: Cryptographic key compromise due to unvalidated Diffie-Hellman peer value [fedora-all]
bugzilla·2026-08-17·CVSS 9.3
CVE-2026-59650 [CRITICAL] CVE-2026-59650 bouncycastle: Bouncy Castle for Java: Cryptographic key compromise due to unvalidated Diffie-Hellman peer value [fedora-all]
CVE-2026-59650 bouncycastle: Bouncy Castle for Java: Cryptographic key compromise due to unvalidated Diffie-Hellman peer value [fedora-all]
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
In Bouncy Castle for Java before 1.85, MTI/A0 DH agreement exponentiates unvalidated peer value. This issue also affects Bouncy Castle for Java LTS before 2.73.12.
Bugzilla
CVE-2026-59650 bouncycastle: Bouncy Castle for Java: Cryptographic key compromise due to unvalidated Diffie-Hellman peer value [epel-all]
bugzilla·2026-08-17·CVSS 9.3
CVE-2026-59650 [CRITICAL] CVE-2026-59650 bouncycastle: Bouncy Castle for Java: Cryptographic key compromise due to unvalidated Diffie-Hellman peer value [epel-all]
CVE-2026-59650 bouncycastle: Bouncy Castle for Java: Cryptographic key compromise due to unvalidated Diffie-Hellman peer value [epel-all]
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
In Bouncy Castle for Java before 1.85, MTI/A0 DH agreement exponentiates unvalidated peer value. This issue also affects Bouncy Castle for Java LTS before 2.73.12.
Bugzilla
CVE-2026-59650 bouncycastle: Bouncy Castle for Java: Cryptographic key compromise due to unvalidated Diffie-Hellman peer value
bugzilla·2026-08-03·CVSS 9.3
CVE-2026-59650 [CRITICAL] CVE-2026-59650 bouncycastle: Bouncy Castle for Java: Cryptographic key compromise due to unvalidated Diffie-Hellman peer value
CVE-2026-59650 bouncycastle: Bouncy Castle for Java: Cryptographic key compromise due to unvalidated Diffie-Hellman peer value
In Bouncy Castle for Java before 1.85, MTI/A0 DH agreement exponentiates unvalidated peer value. This issue also affects Bouncy Castle for Java LTS before 2.73.12.
2026-08-03
Published