An integer underflow in FRRouting (FRR) stable/10.0 to stable/10.6 allows attackers to cause a Denial of Service (DoS) via supplying a crafted BGP UPDATE message.

The remote AlmaLinux 10 host has packages installed that are affected by multiple vulnerabilities as referenced in the ALSA-2026:24347 advisory.

    * frr: denial of service via crafted FlowSpec component (CVE-2026-37457)
      * frr: denial of service via crafted BGP UPDATE message (CVE-2026-37459)

Tenable has extracted the preceding description block directly from the AlmaLinux 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 AlmaLinux 9 host has packages installed that are affected by multiple vulnerabilities as referenced in the ALSA-2026:24370 advisory.

    * frr: denial of service via crafted FlowSpec component (CVE-2026-37457)
      * frr: denial of service via crafted BGP UPDATE message (CVE-2026-37459)

Tenable has extracted the preceding description block directly from the AlmaLinux 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 Oracle Linux 9 host has packages installed that are affected by multiple vulnerabilities as referenced in the ELSA-2026-24370 advisory.

    [10.4.3-3]
    - Resolves: RHEL-174696 - denial of service via crafted BGP UPDATE message

    [10.4.3-2]
    - Resolves: RHEL-174678 - denial of service via crafted FlowSpec component

Tenable has extracted the preceding description block directly from the Oracle Linux 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 packages installed that are affected by multiple vulnerabilities as referenced in the FEDORA-2026-28949d21e5 advisory.

    New version of frr and grout. I am keeping libyang to version 3 at the moment due to recommendations from     https://github.com/FRRouting/frr/blob/master/doc/developer/building-libyang.rst. Once changes to build     with libyang5 land, I will rebase libyang as well.

Tenable has extracted the preceding description block directly from the Fedora 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 RockyLinux 10 host has packages installed that are affected by multiple vulnerabilities as referenced in the RLSA-2026:24347 advisory.

    * frr: denial of service via crafted FlowSpec component (CVE-2026-37457)

    * frr: denial of service via crafted BGP UPDATE message (CVE-2026-37459)

Tenable has extracted the preceding description block directly from the RockyLinux 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 RockyLinux 9 host has packages installed that are affected by multiple vulnerabilities as referenced in the RLSA-2026:24370 advisory.

    * frr: denial of service via crafted FlowSpec component (CVE-2026-37457)

    * frr: denial of service via crafted BGP UPDATE message (CVE-2026-37459)

Tenable has extracted the preceding description block directly from the RockyLinux 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 Redhat Enterprise Linux 9 host has packages installed that are affected by multiple vulnerabilities as referenced in the RHSA-2026:24370 advisory.

    FRRouting is free software that manages TCP/IP based routing protocols. It takes a multi-server and multi-     threaded approach to resolve the current complexity of the Internet.  FRRouting supports BGP4, OSPFv2,     OSPFv3, ISIS, RIP, RIPng, PIM, NHRP, PBR, EIGRP and BFD.  FRRouting is a fork of Quagga.

    Security Fix(es):

    * frr: denial of service via crafted FlowSpec component (CVE-2026-37457)

    * frr: denial of service via crafted BGP UPDATE message (CVE-2026-37459)

    For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and     other related information, refer to the CVE page(s) listed in the References section.

Tenable has extracted the preceding description block directly from the Red Hat Enterprise Linux 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 Redhat Enterprise Linux 10 host has packages installed that are affected by multiple vulnerabilities as referenced in the RHSA-2026:24347 advisory.

    FRRouting is free software that manages TCP/IP based routing protocols. It supports BGP4, OSPFv2, OSPFv3,     ISIS, RIP, RIPng, PIM, NHRP, PBR, EIGRP and BFD.

    Security Fix(es):

    * frr: denial of service via crafted FlowSpec component (CVE-2026-37457)

    * frr: denial of service via crafted BGP UPDATE message (CVE-2026-37459)

    For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and     other related information, refer to the CVE page(s) listed in the References section.

Tenable has extracted the preceding description block directly from the Red Hat Enterprise Linux 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 Ubuntu 22.04 LTS / 24.04 LTS / 25.10 / 26.04 LTS host has packages installed that are affected by multiple vulnerabilities as referenced in the USN-8376-1 advisory.

    It was discovered that FRR incorrectly handled certain OSPF Traffic Engineering and Segment Routing TLVs.
    An attacker could possibly use this issue to cause FRR to crash, resulting in a denial of service.
    (CVE-2026-28532)

    It was discovered that FRR incorrectly handled certain BGP FlowSpec components. An attacker could possibly     use this issue to cause FRR to crash, resulting in a denial of service. (CVE-2026-37457)

    It was discovered that FRR did not properly validate certain MP_REACH_NLRI messages. An authenticated user     could possibly use this issue to cause FRR to crash, resulting in a denial of service. (CVE-2026-37458)

    It was discovered that FRR incorrectly handled processing certain BGP UPDATE messages. An attacker could     possibly use this issue to cause FRR to crash, resulting in a denial of service. This issue only affected     Ubuntu 25.04 and Ubuntu 25.10. (CVE-2026-37459)

Tenable has extracted the preceding description block directly from the Ubuntu 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 Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - An integer underflow in FRRouting (FRR) stable/10.0 to stable/10.6 allows attackers to cause a Denial of     Service (DoS) via supplying a crafted BGP UPDATE message. (CVE-2026-37459)

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

ID	Name	Product	Family	Severity
325763	AlmaLinux 10 : frr (ALSA-2026:24347)	Nessus	Alma Linux Local Security Checks	high
324819	AlmaLinux 9 : frr10 (ALSA-2026:24370)	Nessus	Alma Linux Local Security Checks	high
322993	Oracle Linux 9 : frr10 (ELSA-2026-24370)	Nessus	Oracle Linux Local Security Checks	high
322353	Fedora 44 : frr / grout (2026-28949d21e5)	Nessus	Fedora Local Security Checks	high
320612	RockyLinux 10 : frr (RLSA-2026:24347)	Nessus	Rocky Linux Local Security Checks	high
320607	RockyLinux 9 : frr10 (RLSA-2026:24370)	Nessus	Rocky Linux Local Security Checks	high
319704	RHEL 9 : frr10 (RHSA-2026:24370)	Nessus	Red Hat Local Security Checks	high
319644	RHEL 10 : frr (RHSA-2026:24347)	Nessus	Red Hat Local Security Checks	high
318637	Ubuntu 22.04 LTS / 24.04 LTS / 25.10 / 26.04 LTS : FRR vulnerabilities (USN-8376-1)	Nessus	Ubuntu Local Security Checks	medium
312602	Linux Distros Unpatched Vulnerability : CVE-2026-37459	Nessus	Misc.	high

Detections

Analytics

CVE-2026-37459

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Tenable Plugins

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