CVE-2025-30258

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."

GnuPG is a complete and free implementation of the OpenPGP standard as defined by RFC4880 (also known as PGP). GnuPG enables encryption and signing of data and communication, and features a versatile key management system as well as access modules for public key directories.

Security Fix(es):

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-2025-30258)

GnuPG is a complete and free implementation of the OpenPGP standard as defined by RFC4880 (also known as PGP). GnuPG enables encryption and signing of data and communication, and features a versatile key management system as well as access modules for public key directories.

Security Fix(es):

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-2025-30258)

GnuPG is a complete and free implementation of the OpenPGP standard as defined by RFC4880 (also known as PGP). GnuPG enables encryption and signing of data and communication, and features a versatile key management system as well as access modules for public key directories.

Security Fix(es):

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-2025-30258)

GnuPG is a complete and free implementation of the OpenPGP standard as defined by RFC4880 (also known as PGP). GnuPG enables encryption and signing of data and communication, and features a versatile key management system as well as access modules for public key directories.

Security Fix(es):

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-2025-30258)

GnuPG is a complete and free implementation of the OpenPGP standard as defined by RFC4880 (also known as PGP). GnuPG enables encryption and signing of data and communication, and features a versatile key management system as well as access modules for public key directories.

Security Fix(es):

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-2025-30258)

Root has patched CVE-2025-30258 in the gnupg2 package for Root:Debian:11. Multiple fixed versions available.

Root has patched CVE-2025-30258 in the gnupg2 package for Root:Debian:12. Multiple fixed versions available.

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."

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."

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-2025-30258: fix verification DoS due to a malicious subkey in the keyring

• CVE-2025-30258: fix verification DoS due to a malicious subkey in the keyring

• SECURITY UPDATE: signature verification DoS via malicious subkey
  • debian/patches/CVE-2025-30258.patch: require signing usage when looking up public key for signature verification, filtering out subkeys without valid backsig. Include upstream regression fixes to preserve verification of signatures from expired/revoked keys. Widen pubkey_usage and req_usage fields from byte to u16 to prevent PUBKEY_USAGE_VERIFY (16384) from being truncated on GnuPG 2.2.x. Add primary-key-only lookup during import to prevent malicious subkey attack at import time. Fix double-free in check_signature_over_key_or_uid when signer is caller-owned.
  • CVE-2025-30258

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-2025-30258)

These are all security issues fixed in the dirmngr-2.5.6-1.1 package on the GA media of openSUSE Tumbleweed.

This update for gpg2 fixes the following issues:

This reverts the CVE-2025-30258 fix, as it changed behaviour when using expired keys.

This update for gpg2 fixes the following issues:

• CVE-2025-30258: Fixed DoS due to a malicious subkey in the keyring (bsc#1239119).

Other bugfixes:

• Do not install expired sks certificate (bsc#1243069).
• gpg hangs when importing a key (bsc#1236931).

This update for gpg2 fixes the following issues:

• CVE-2025-30258: Fixed DoS due to a malicious subkey in the keyring (bsc#1239119)

This update for gpg2 fixes the following issues:

• CVE-2025-30258: Fixed a verification DoS due to a malicious subkey in the keyring. (bsc#1239119)

This update for gpg2 fixes the following issues:

• Fix regression for the recent malicious subkey DoS fix in CVE-2025-30258. [bsc#1236931, bsc#1239119, CVE-2025-30258]

This update for gpg2 fixes the following issues:

• Fixed regressions for the recent malicious subkey DoS fix for CVE-2025-30258 (bsc#1239119).

This update for gpg2 fixes the following issues:

• gpg: Allow the use of an ADSK subkey as ADSK subkey. (bsc#1239119 CVE-2025-30258)
• Don't install expired sks certificate [bsc#1243069]

This update for gpg2 fixes the following issues:

• CVE-2025-30258: Fix a verification DoS due to a malicious subkey in the keyring: [bsc#1239119, bsc#1236931]]

  • gpg: Fix regression for the recent malicious subkey DoS fix.
  • gpg: Fix another regression due to the T7547 fix.
  • gpg: Allow the use of an ADSK subkey as ADSK subkey.

• Don't install expired sks certificate [bsc#1243069]

This update for gpg2 fixes the following issues:

• CVE-2025-30258: fixed a verification denial of service due to a malicious subkey in the keyring (bsc#1239119)

It was discovered that GnuPG incorrectly handled importing keys with certain crafted subkey data. If a user or automated system were tricked into importing a specially crafted key, a remote attacker may prevent users from importing other keys in the future.

USN-7412-1 fixed a vulnerability in GnuPG. This update provides the corresponding update for Ubuntu 16.04 LTS and Ubuntu 18.04 LTS.

Original advisory details:

It was discovered that GnuPG incorrectly handled importing keys with certain crafted subkey data. If a user or automated system were tricked into importing a specially crafted key, a remote attacker may prevent users from importing other keys in the future.