Vulnerability · Published Jul 16, 2026 · Assigned by bcorg
CVE-2026-15997Native ARM SHA3 / SHAKE `restoreFullState` fails to detect size_t underflow in a crafted encoded state
Low 1.7
In plain English
A low-severity out-of-bounds write in BC-LTS from Legion of the Bouncy Castle Inc.. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.1% (higher than 3% of all known vulnerabilities).
Official description
Out-of-bounds write vulnerability in Legion of the Bouncy Castle Inc. BC-LTS bcprov-lts8on on ARM allows Overflow Buffers. This vulnerability is associated with program files https://github.Com/bcgit/bc-lts-java/blob/main/native_c/arm/sha/shake.C, https://github.Com/bcgit/bc-lts-java/blob/main/native_c/arm/sha/sha3.C. This issue affects BC-LTS: from 2.73.0 before 2.73.12.1. Issue is only applicable if application involved is accepting memoable SHA3 / SHAKE states from potentially untrusted sources.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu:26.04:LTS | bouncycastle | no fix listed | UBUNTU-CVE-2026-15997 |
| Ubuntu:26.10 | bouncycastle | no fix listed | UBUNTU-CVE-2026-15997 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Legion of the Bouncy Castle Inc. | BC-LTS | 2.73.0 – before 2.73.12.1 |
Weakness: CWE-787 · Vector: CVSS:4.0/AV:L/AC:H/AT:P/PR:N/UI:A/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/S:P/AU:N/R:A/V:D/RE:M/U:Amber