USN-3675-1: GnuPG vulnerabilities

Releases

• Ubuntu 18.04 ESM
• Ubuntu 17.10
• Ubuntu 16.04 ESM
• Ubuntu 14.04 ESM

Packages

• gnupg - GNU privacy guard - a free PGP replacement
• gnupg2 - GNU privacy guard - a free PGP replacement

Details

Marcus Brinkmann discovered that during decryption or verification,
GnuPG did not properly filter out terminal sequences when reporting the
original filename. An attacker could use this to specially craft a file
that would cause an application parsing GnuPG output to incorrectly
interpret the status of the cryptographic operation reported by GnuPG.
(CVE-2018-12020)

Lance Vick discovered that GnuPG did not enforce configurations where
key certification required an offline primary Certify key. An attacker
with access to a signing subkey could generate certifications that
appeared to be valid. This issue only affected Ubuntu 18.04 LTS.
(CVE-2018-9234)

Update instructions

The problem can be corrected by updating your system to the following package versions:

Ubuntu 18.04

• gnupg - 2.2.4-1ubuntu1.1
• gpg - 2.2.4-1ubuntu1.1

Ubuntu 17.10

• gnupg - 2.1.15-1ubuntu8.1

Ubuntu 16.04

• gnupg - 1.4.20-1ubuntu3.2

Ubuntu 14.04

• gnupg - 1.4.16-1ubuntu2.5

In general, a standard system update will make all the necessary changes.

References

• CVE-2018-12020
• CVE-2018-9234

Related notices

• USN-3675-3: gnupg
• USN-3675-2: dirmngr, gnupg-agent, gpgv-udeb, scdaemon, gpgsm, gnupg2, gpgv2
• USN-3964-1: python-gnupg, python3-gnupg
• USN-4839-1: python-gnupg, python3-gnupg