Disclosure summary
In GnuPG before 2.5.5, if a user chooses to import a certificate with certain crafted subkey data that lacks a valid backsig or that has incorrect usage flags, the user loses the ability to verify signatures made from certain other signing keys, aka a "verification DoS."
Source-reported weakness categories
CWE-754
Source-specific records & product guidance
Sources retain their own attribution and scoring. Follow the original record to confirm affected versions, fixed releases, and configuration conditions.
Microsoft Security Updates (CVRF) · 2025-Mar
Open original source · Updated Oct 07, 2026
In GnuPG before 2.5.5, if a user chooses to import a certificate with certain crafted subkey data that lacks a valid backsig or that has incorrect usage flags, the user loses the ability to verify signatures made from certain other signing keys, aka a "verification DoS."
Maximum of vendor-reported product scores; products and fixed builds are associations, not a universal affected-version statement.
Microsoft maximum product score: 2.7
| Vendor | Product / association | Version / bounds |
|---|---|---|
| Microsoft update guide | cbl2 gnupg2 2.4.0-3 on CBL-Mariner 2.0 | (MSRC status code 3) |
| Microsoft update guide | cbl2 gnupg2 2.4.0-2 on CBL Mariner 2.0 | (MSRC status code 3) |
| Microsoft update guide | azl3 gnupg2 2.4.7-1 on Azure Linux 3.0 | (MSRC status code 3) |
| Microsoft update guide | azl3 gnupg2 2.4.9-1 on Azure Linux 3.0 | (MSRC status code 3) |
| Microsoft update guide | azl3 gnupg2 2.4.9-2 on Azure Linux 3.0 | (MSRC status code 3) |
| Microsoft update guide | cbl2 gnupg2 2.4.0-3 on CBL Mariner 2.0 | (MSRC status code 3) |
Vendor remediation references
- Release Notes · product IDs 20945-21692
- Vendor guidance · product IDs 20945-21692
- CBL-Mariner Releases · build 2.4.8-1 · product IDs 20904-17084
- Vendor guidance · product IDs 20904-17084
Original records & references
- NIST NVD record
- CVE Program record
- msrc.microsoft.com — Vendor advisory
PUBLISHED 2025-09-03T23:09:31-04:00
MODIFIED 2026-10-07T21:50:07-04:00
INGESTED 2026-10-08T12:50:09-04:00