Improper link resolution before file access ('link following') vulnerability in the `tar` source plugin of Apache BuildStream running on Python < 3.12 allows malicious source tarballs to write files on the host, with the privileges of the user running BuildStream, via symlinks as part of source fetching. The impact of this issue is mitigated by: * BuildStream projects should only use trusted sources in their elements as otherwise the build output can also not be trusted * Tracking a source tarball pins its SHA256 hash, which prevents MITM attacks of users that are fetching an already tracked project * When running on Python >= 3.12, BuildStream >= 2.3.0 already makes use of the Python `tarfile` filter functionality, which blocks the symlink escape Users are recommended to upgrade to version 2.8.1, which fixes this issue.

The remote Debian 13 host has packages installed that are affected by a vulnerability as referenced in the dsa-6559 advisory.

    - -------------------------------------------------------------------------     Debian Security Advisory DSA-6559-1                   security@debian.org     https://www.debian.org/security/                       Moritz Muehlenhoff     October 14, 2026                      https://www.debian.org/security/faq
    - -------------------------------------------------------------------------

    Package        : buildstream     CVE ID         : CVE-2026-82331

    It was discovered that missing validation of tar sources in the     Buildstream software integration tool could allow to write files on the     build host.

    For the stable distribution (trixie), this problem has been fixed in     version 1.6.9-2+deb13u1.

    We recommend that you upgrade your buildstream packages.

    For the detailed security status of buildstream please refer to     its security tracker page at:
    https://security-tracker.debian.org/tracker/buildstream

    Further information about Debian Security Advisories, how to apply     these updates to your system and frequently asked questions can be     found at: https://www.debian.org/security/

    Mailing list: debian-security-announce@lists.debian.org

Tenable has extracted the preceding description block directly from the Debian security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

The remote Fedora 43 host has a package installed that is affected by a vulnerability as referenced in the FEDORA-2026-e14ea5695c advisory.

    CVE-2026-82331 (CWE-59): tar source plugin symlink escape while fetching     a malicious tarball (Python < 3.12). Fixed upstream in 2.8.1     (tar.py extraction filter, #2192).

    Fedora's system python3 is >= 3.12, so the packaged /usr/bin/bst was     already using tarfile filters. This update still ships 2.8.1 so     BuildStream run on older parallel Pythons (venv / pip / python3.11)     is covered.

    Recommend buildstream-plugins-community as well.


Tenable has extracted the preceding description block directly from the Fedora security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

The remote Fedora 44 host has a package installed that is affected by a vulnerability as referenced in the FEDORA-2026-ccf62cb9b3 advisory.

    CVE-2026-82331 (CWE-59): tar source plugin symlink escape while fetching     a malicious tarball (Python < 3.12). Fixed upstream in 2.8.1     (tar.py extraction filter, #2192).

    Fedora's system python3 is >= 3.12, so the packaged /usr/bin/bst was     already using tarfile filters. This update still ships 2.8.1 so     BuildStream run on older parallel Pythons (venv / pip / python3.11)     is covered.

    Recommend buildstream-plugins-community as well.


Tenable has extracted the preceding description block directly from the Fedora security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

The remote Fedora 45 host has a package installed that is affected by a vulnerability as referenced in the FEDORA-2026-d77557766a advisory.

    CVE-2026-82331 (CWE-59): tar source plugin symlink escape while fetching     a malicious tarball (Python < 3.12). Fixed upstream in 2.8.1     (tar.py extraction filter, #2192).

    Fedora's system python3 is >= 3.12, so the packaged /usr/bin/bst was     already using tarfile filters. This update still ships 2.8.1 so     BuildStream run on older parallel Pythons (venv / pip / python3.11)     is covered.

    Recommend buildstream-plugins-community as well.


Tenable has extracted the preceding description block directly from the Fedora security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - Improper link resolution before file access ('link following') vulnerability in the `tar` source plugin of     Apache BuildStream running on Python < 3.12 allows malicious source tarballs to write files on the host,     with the privileges of the user running BuildStream, via symlinks as part of source fetching. The impact     of this issue is mitigated by: * BuildStream projects should only use trusted sources in their elements as     otherwise the build output can also not be trusted * Tracking a source tarball pins its SHA256 hash, which     prevents MITM attacks of users that are fetching an already tracked project * When running on Python >=     3.12, BuildStream >= 2.3.0 already makes use of the Python `tarfile` filter functionality, which blocks     the symlink escape Users are recommended to upgrade to version 2.8.1, which fixes this issue.
    (CVE-2026-82331)

Note that Nessus relies on the presence of the package as reported by the vendor.

ID	Name	Product	Family	Type	Severity
365636	Debian dsa-6559 : buildstream - security update	Nessus	Debian Local Security Checks	Local	critical
362837	Fedora 43 : buildstream (2026-e14ea5695c)	Nessus	Fedora Local Security Checks	Local	critical
362815	Fedora 44 : buildstream (2026-ccf62cb9b3)	Nessus	Fedora Local Security Checks	Local	critical
362718	Fedora 45 : buildstream (2026-d77557766a)	Nessus	Fedora Local Security Checks	Local	critical
349505	Linux Distros Unpatched Vulnerability : CVE-2026-82331	Nessus	Misc.	Local	critical

Detections

Analytics

CVE-2026-82331

critical

Tenable Plugins

critical

critical

critical

critical

critical