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."
CVE ID: CVE-2025-30258
CVSS Base Severity: LOW
CVSS Base Score: 2.7
CVSS Vector: CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:C/C:N/I:N/A:L
Vendor: GnuPG
Product: GnuPG
EPSS Score: 0.01% (probability of being exploited)
EPSS Percentile: 0.66% (scored less or equal to compared to others)
EPSS Date: 2025-04-17 (when was this score calculated)