RRSIGs with too few labels can lead to bypass of DNSSEC wildcard validation

The remote Debian 13 host has a package installed that is affected by multiple vulnerabilities as referenced in the dsa-6397 advisory.

    - -------------------------------------------------------------------------     Debian Security Advisory DSA-6397-1                   security@debian.org     https://www.debian.org/security/                     Salvatore Bonaccorso     July 23, 2026                         https://www.debian.org/security/faq
    - -------------------------------------------------------------------------

    Package        : pdns-recursor     CVE ID         : CVE-2026-52686 CVE-2026-52688

    Multiple vulnerabilities have been discovered in PDNS Recursor, a     resolving name server, which could result in cache poisoning or DNSSEC     validation bypass.

    For the stable distribution (trixie), these problems have been fixed in     version 5.2.12-0+deb13u1.

    We recommend that you upgrade your pdns-recursor packages.

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

    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 these issues 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-ae048e451f advisory.

    Update to 5.4.6

    Resolves: rhbz#2527899


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-2026-6c1e0af917 advisory.

    Update to 5.4.6

    Resolves: rhbz#2527899


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.

There are packages installed that are affected by multiple vulnerabilities referenced in the following CVEs:

  - The issue is a DNSSEC validation bypass where wildcard expansion proofs (NSEC/NSEC3 records) are accepted
    without signature validation when the wildcard answer is a CNAME or DNAME record. (CVE-2026-52686)

  - RRSIGs with too few labels can lead to bypass of DNSSEC wildcard validation (CVE-2026-52688)

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

  - RRSIGs with too few labels can lead to bypass of DNSSEC wildcard validation (CVE-2026-52688)

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

ID	Name	Product	Family	Type	Severity
349324	Debian dsa-6397 : pdns-recursor - security update	Nessus	Debian Local Security Checks	Local	high
345472	Fedora 44 : pdns-recursor (2026-ae048e451f)	Nessus	Fedora Local Security Checks	Local	high
345462	Fedora 45 : pdns-recursor (2026-6c1e0af917)	Nessus	Fedora Local Security Checks	Local	high
445412	Alpine: multiple pdns-recursor packages: security update to 5.4.4-r0	Tenable Cloud Security	Alpine Linux Local Security Checks	Local	high
445412	Alpine: multiple pdns-recursor packages: security update to 5.4.4-r0	Tenable Self-Hosted Container Security	Alpine Linux Local Security Checks	Local	high
329616	Linux Distros Unpatched Vulnerability : CVE-2026-52688	Nessus	Misc.	Local	high

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