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Security Advisory

USN-5550-1: GnuTLS vulnerabilities

USN-5550-1: GnuTLS vulnerabilities




Canonical Ubuntu

Versions Affected

  • Canonical Ubuntu 18.04


It was discovered that GnuTLS incorrectly handled certain memory operations. A remote attacker could possibly use this issue to cause GnuTLS to crash, resulting in a denial of service. This issue only affected Ubuntu 18.04 LTS, and Ubuntu 20.04 LTS. (CVE-2021-4209) It was discovered that GnuTLS incorrectly handled the verification of certain pkcs7 signatures. A remote attacker could use this issue to cause GnuTLS to crash, resulting in a denial of service, or possibly execute arbitrary code. (CVE-2022-2509) Update Instructions: Run `sudo ua fix USN-5550-1` to fix the vulnerability. The problem can be corrected by updating your system to the following package versions: libgnutls30 – 3.5.18-1ubuntu1.6 libgnutls28-dev – 3.5.18-1ubuntu1.6 libgnutls-openssl27 – 3.5.18-1ubuntu1.6 gnutls-doc – 3.5.18-1ubuntu1.6 libgnutls-dane0 – 3.5.18-1ubuntu1.6 gnutls-bin – 3.5.18-1ubuntu1.6 libgnutlsxx28 – 3.5.18-1ubuntu1.6 No subscription required

CVEs contained in this USN include: CVE-2021-4209, CVE-2022-2509.

Affected Cloud Foundry Products and Versions

Severity is medium unless otherwise noted.

  • Bionic Stemcells
    • 1.x versions prior to 1.97
    • All other stemcells not listed.
  • cflinuxfs3
    • All versions prior to 0.313.0
  • CF Deployment
    • All versions


Users of affected products are strongly encouraged to follow the mitigations below.

The Cloud Foundry project recommends upgrading the following releases:

  • Bionic Stemcells
    • Upgrade 1.x versions to 1.97 or greater
    • All other stemcells should be upgraded to the latest version available on
  • cflinuxfs3
    • Upgrade all versions to 0.313.0 or greater
  • CF Deployment
    • There are no fixed versions of this product


2022-08-25: Initial vulnerability report published.

Cloud Foundry Foundation Security Team Profile Image

Cloud Foundry Foundation Security Team, AUTHOR