CVE-2026-8149
mediumpriority · track · 0EPSS 0.002 · 5 %ileEUUSEPSS · scored 2026-10-27
A vulnerability in Legion of the Bouncy Castle Inc. BC-LTS bcprov-lts8on on X86_64, AVX, AVX-512f, Linux, Legion of the Bouncy Castle Inc. BC-FJA bc-fips on Linux, X86_64, AVX, AVX-512f. This vulnerability is associated with program files gcm128w, gcm512w, gcm128w.C, gcm512w.C. This issue affects BC-LTS: from 2.73.0 before 2.73.11; BC-FJA: from 2.1.0 before 2.1.3.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · low–medium · 1.2–5.1
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (3)
Products and version ranges known to be affected.
advisories (1)
Vendor and ecosystem advisories describing this.
- GHSA-mx76-r943-rf8gBouncy Castle LTS native GCM chunking can cause bad-tag exception on decryption2026-05-08ghsa · osvUS
In Bouncy Castle LTS for Java, the AES/GCM native implementation used on Intel CPUs with AES PAA instruction sets (AVX / VAES / VAESF variants) can intermittently produce an incorrect authentication tag verification result during decryption when the ciphertext is fed in via a mix of `update()` calls followed by `doFinal()`. It is possible to work around it by either using `doFinal()` only (as the BCJSSE does) or by configuring the module to run in pure Java mode, by setting the system property "org.bouncycastle.native.cpu_variant" to java.
also known as (3)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (5)
External citations — patches, advisories, analysis.
- https://access.redhat.com/security/cve/cve-2026-8149cnnvd
- https://github.com/bcgit/bc-java/wiki/CVE%E2%80%902026%E2%80%908149cnnvd
- https://nvd.nist.gov/vuln/detail/CVE-2026-8149cnnvd
- https://github.com/bcgit/bc-java/wiki/CVE%E2%80%902026%E2%80%908149enisa_euvd
- https://github.com/bcgit/bc-java/wiki/CVE%E2%80%902026%E2%80%908149nvd
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