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Security Advisory

USN-4764-1: GLib vulnerability




Canonical Ubuntu

Versions Affected

  • Canonical Ubuntu 16.04
  • Canonical Ubuntu 18.04


It was discovered that GLib incorrectly handled certain symlinks when replacing files. If a user or automated system were tricked into extracting a specially crafted file with File Roller, a remote attacker could possibly create files outside of the intended directory.

CVEs contained in this USN include: CVE-2021-28153.

Affected Cloud Foundry Products and Versions

Severity is medium unless otherwise noted.

  • cflinuxfs3
    • All versions prior to 0.230.0
  • Xenial Stemcells
    • 456.x versions prior to 456.152
    • 621.x versions prior to 621.115
    • All other stemcells not listed.
  • CF Deployment
    • All versions prior to 16.11.0


Users of affected products are strongly encouraged to follow the mitigations below. The Cloud Foundry project recommends upgrading the following releases:

  • cflinuxfs3
    • Upgrade all versions to 0.230.0 or greater
  • Xenial Stemcells
    • Upgrade 456.x versions to 456.152 or greater
    • Upgrade 621.x versions to 621.115 or greater
    • All other stemcells should be upgraded to the latest version available on
  • CF Deployment
    • Upgrade all versions to 16.11.0 or greater


2021-04-14: Initial vulnerability report published.

Cloud Foundry Foundation Security Team Profile Image

Cloud Foundry Foundation Security Team, AUTHOR