CVE-2026-8149: GCM chunking can lead to bad tag exception on decryption

Published May 8, 2026
·
Updated

A vulnerability in Legion of the Bouncy Castle Inc. BC-LTS bcprov-lts8on on X8664, AVX, AVX-512f, Linux, Legion of the Bouncy Castle Inc. BC-FJA bc-fips on Linux, X8664, 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.

Affected Software

3 affected components
Legion of the Bouncy Castle Inc. BC-LTS bcprov-lts8on>=2.73.0<2.73.11
Legion of the Bouncy Castle Inc. BC-FJA bc-fips>=2.1.0<2.1.3
IBM Concert Software<=1.0.0-3.0.0

Event History

May 8, 2026
CVE Published
via MITRE·06:01 AM
Data Sourced
via MITRE·06:01 AM
DescriptionWeakness
Data Sourced
via NVD·07:16 AM
DescriptionSeverityWeakness
Sep 22, 2026
Data Sourced
via IBM·12:00 AM
DescriptionAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Frequently Asked Questions

1

What is the severity of CVE-2026-8149?

CVE-2026-8149 has a high severity due to potential decryption failures caused by bad tag exceptions.

2

How do I fix CVE-2026-8149?

To fix CVE-2026-8149, upgrade the Bouncy Castle BC-FJA library to version 2.1.3 or later.

3

What software is affected by CVE-2026-8149?

CVE-2026-8149 affects Bouncy Castle BC-FJA versions from 2.1.0 through 2.1.2.

4

What types of systems are impacted by CVE-2026-8149?

CVE-2026-8149 primarily impacts Linux systems running on x86_64 with AVX and AVX-512f.

5

What function of Bouncy Castle is vulnerable in CVE-2026-8149?

CVE-2026-8149 involves a vulnerability in the GCM chunking functionality during decryption.

Contact

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