NLnet Labs Unbound up to and including version 1.21.0 contains a vulnerability when handling replies with very large RRsets that it needs to perform name compression for. Malicious upstreams responses with very large RRsets can cause Unbound to spend a considerable time applying name compression to downstream replies. This can lead to degraded performance and eventually denial of service in well orchestrated attacks. The vulnerability can be exploited by a malicious actor querying Unbound for the specially crafted contents of a malicious zone with very large RRsets. Before Unbound replies to the query it will try to apply name compression which was an unbounded operation that could lock the CPU until the whole packet was complete. Unbound version 1.21.1 introduces a hard limit on the number of name compression calculations it is willing to do per packet. Packets that need more compression will result in semi-compressed packets or truncated packets, even on TCP for huge messages, to avoid locking the CPU for long. This change should not affect normal DNS traffic.

The remote Fedora 41 host has a package installed that is affected by multiple vulnerabilities as referenced in the FEDORA-2024-a5d6cd9f0a advisory.

    Fixed builds on F41. Fixes  CVE-2024-8508

    - https://github.com/NLnetLabs/unbound/releases/tag/release-1.21.1


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 Debian 11 host has packages installed that are affected by a vulnerability as referenced in the dla-3952 advisory.

    -------------------------------------------------------------------------     Debian LTS Advisory DLA-3952-1                debian-lts@lists.debian.org     https://www.debian.org/lts/security/                       Daniel Leidert     November 14, 2024                             https://wiki.debian.org/LTS
    -------------------------------------------------------------------------

    Package        : unbound     Version        : 1.13.1-1+deb11u4     CVE ID         : CVE-2024-8508     Debian Bug     : 1083282

    A vulnerability has been discovered in unbound, a validating,     recursive, caching DNS resolver. Malicious upstreams responses with     very large RRsets can cause Unbound to spend a considerable time     applying name compression to downstream replies. This can lead to     degraded performance and eventually denial of service in well     orchestrated attacks. The vulnerability can be exploited by a malicious     actor querying Unbound for the specially crafted contents of a     malicious zone with very large RRsets.

    For Debian 11 bullseye, this problem has been fixed in version     1.13.1-1+deb11u4.

    We recommend that you upgrade your unbound packages.

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

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

    Attachment:
    signature.asc     Description: This is a digitally signed message part

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.

An update of the unbound package has been released.

The remote Ubuntu 14.04 LTS / 16.04 LTS / 18.04 LTS / 20.04 LTS / 22.04 LTS / 24.04 LTS / 24.10 host has packages installed that are affected by a vulnerability as referenced in the USN-7080-1 advisory.

    Toshifumi Sakaguchi discovered that Unbound incorrectly handled name

    compression for large RRsets, which could lead to excessive CPU usage.

    An attacker could potentially use this issue to cause a denial of service by sending specially crafted DNS     responses.

Tenable has extracted the preceding description block directly from the Ubuntu 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 39 host has a package installed that is affected by multiple vulnerabilities as referenced in the FEDORA-2024-2ba00c906c advisory.

    Fixed builds on F41. Fixes  CVE-2024-8508

    - https://github.com/NLnetLabs/unbound/releases/tag/release-1.21.1



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 SUSE Linux SLED15 / SLED_SAP15 / SLES15 / SLES_SAP15 / openSUSE 15 host has packages installed that are affected by a vulnerability as referenced in the SUSE-SU-2024:3647-1 advisory.

    - CVE-2024-8508: Fixed unbounded name compression that could lead to denial of service (bsc#1231284)

Tenable has extracted the preceding description block directly from the SUSE 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 SUSE Linux SLED15 / SLED_SAP15 / SLES15 / SLES_SAP15 / openSUSE 15 host has packages installed that are affected by a vulnerability as referenced in the SUSE-SU-2024:3646-1 advisory.

    - CVE-2024-8508: Fixed unbounded name compression that could lead to denial of service (bsc#1231284)

Tenable has extracted the preceding description block directly from the SUSE 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 version of unbound installed on the remote host is prior to 1.7.3-15. It is, therefore, affected by a vulnerability as referenced in the ALAS2-2024-2650 advisory.

    NLnet Labs Unbound up to and including version 1.21.0 contains a vulnerability when handling replies with     very large RRsets that it needs to perform name compression for. Malicious upstreams responses with very     large RRsets can cause Unbound to spend a considerable time applying name compression to downstream     replies. This can lead to degraded performance and eventually denial of service in well orchestrated     attacks. The vulnerability can be exploited by a malicious actor querying Unbound for the specially     crafted contents of a malicious zone with very large RRsets. Before Unbound replies to the query it will     try to apply name compression which was an unbounded operation that could lock the CPU until the whole     packet was complete. Unbound version 1.21.1 introduces a hard limit on the number of name compression     calculations it is willing to do per packet. Packets that need more compression will result in semi-     compressed packets or truncated packets, even on TCP for huge messages, to avoid locking the CPU for long.
    This change should not affect normal DNS traffic. (CVE-2024-8508)

Tenable has extracted the preceding description block directly from the tested product 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 version of unbound installed on the remote host is prior to 1.17.0-2. It is, therefore, affected by a vulnerability as referenced in the ALAS2UNBOUND-1.17-2024-003 advisory.

    NLnet Labs Unbound up to and including version 1.21.0 contains a vulnerability when handling replies with     very large RRsets that it needs to perform name compression for. Malicious upstreams responses with very     large RRsets can cause Unbound to spend a considerable time applying name compression to downstream     replies. This can lead to degraded performance and eventually denial of service in well orchestrated     attacks. The vulnerability can be exploited by a malicious actor querying Unbound for the specially     crafted contents of a malicious zone with very large RRsets. Before Unbound replies to the query it will     try to apply name compression which was an unbounded operation that could lock the CPU until the whole     packet was complete. Unbound version 1.21.1 introduces a hard limit on the number of name compression     calculations it is willing to do per packet. Packets that need more compression will result in semi-     compressed packets or truncated packets, even on TCP for huge messages, to avoid locking the CPU for long.
    This change should not affect normal DNS traffic. (CVE-2024-8508)

Tenable has extracted the preceding description block directly from the tested product 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 version of unbound installed on the remote host is prior to 1.13.1-3. It is, therefore, affected by a vulnerability as referenced in the ALAS2UNBOUND-2024-003 advisory.

    NLnet Labs Unbound up to and including version 1.21.0 contains a vulnerability when handling replies with     very large RRsets that it needs to perform name compression for. Malicious upstreams responses with very     large RRsets can cause Unbound to spend a considerable time applying name compression to downstream     replies. This can lead to degraded performance and eventually denial of service in well orchestrated     attacks. The vulnerability can be exploited by a malicious actor querying Unbound for the specially     crafted contents of a malicious zone with very large RRsets. Before Unbound replies to the query it will     try to apply name compression which was an unbounded operation that could lock the CPU until the whole     packet was complete. Unbound version 1.21.1 introduces a hard limit on the number of name compression     calculations it is willing to do per packet. Packets that need more compression will result in semi-     compressed packets or truncated packets, even on TCP for huge messages, to avoid locking the CPU for long.
    This change should not affect normal DNS traffic. (CVE-2024-8508)

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

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

It is, therefore, affected by a vulnerability as referenced in the ALAS2023-2024-719 advisory.

    NLnet Labs Unbound up to and including version 1.21.0 contains a vulnerability when handling replies with     very large RRsets that it needs to perform name compression for. Malicious upstreams responses with very     large RRsets can cause Unbound to spend a considerable time applying name compression to downstream     replies. This can lead to degraded performance and eventually denial of service in well orchestrated     attacks. The vulnerability can be exploited by a malicious actor querying Unbound for the specially     crafted contents of a malicious zone with very large RRsets. Before Unbound replies to the query it will     try to apply name compression which was an unbounded operation that could lock the CPU until the whole     packet was complete. Unbound version 1.21.1 introduces a hard limit on the number of name compression     calculations it is willing to do per packet. Packets that need more compression will result in semi-     compressed packets or truncated packets, even on TCP for huge messages, to avoid locking the CPU for long.
    This change should not affect normal DNS traffic. (CVE-2024-8508)

Tenable has extracted the preceding description block directly from the tested product 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 version of unbound installed on the remote CBL Mariner 2.0 host is prior to tested version. It is, therefore, affected by a vulnerability as referenced in the CVE-2024-8508 advisory.

  - NLnet Labs Unbound up to and including version 1.21.0 contains a vulnerability when handling replies with     very large RRsets that it needs to perform name compression for. Malicious upstreams responses with very     large RRsets can cause Unbound to spend a considerable time applying name compression to downstream     replies. This can lead to degraded performance and eventually denial of service in well orchestrated     attacks. The vulnerability can be exploited by a malicious actor querying Unbound for the specially     crafted contents of a malicious zone with very large RRsets. Before Unbound replies to the query it will     try to apply name compression which was an unbounded operation that could lock the CPU until the whole     packet was complete. Unbound version 1.21.1 introduces a hard limit on the number of name compression     calculations it is willing to do per packet. Packets that need more compression will result in semi-     compressed packets or truncated packets, even on TCP for huge messages, to avoid locking the CPU for long.
    This change should not affect normal DNS traffic. (CVE-2024-8508)

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

The version of FreeBSD installed on the remote host is prior to tested version. It is, therefore, affected by a vulnerability as referenced in the 2368755b-83f6-11ef-8d2e-a04a5edf46d9 advisory.

    NLnet labs report:
    A vulnerability has been discovered in Unbound when handling                 replies with very large RRsets that Unbound needs to perform name                 compression for.
    Malicious upstreams responses with very large RRsets can cause                 Unbound to spend a considerable time applying name compression to                 downstream replies. This can lead to degraded performance and                 eventually denial of service in well orchestrated attacks.
    Unbound version 1.21.1 introduces a hard limit on the number of                 name compression calculations it is willing to do per packet.
                Packets that need more compression will result in semi-compressed                 packets or truncated packets, even on TCP for huge messages, to                 avoid locking the CPU for long.
    This change should not affect normal DNS traffic.

Tenable has extracted the preceding description block directly from the FreeBSD 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 40 host has a package installed that is affected by multiple vulnerabilities as referenced in the FEDORA-2024-c07e065747 advisory.

    Fixes  CVE-2024-8508

    - https://github.com/NLnetLabs/unbound/releases/tag/release-1.21.1



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.

ID	Name	Product	Family	Severity
211417	Fedora 41 : unbound (2024-a5d6cd9f0a)	Nessus	Fedora Local Security Checks	medium
211384	Debian dla-3952 : libunbound-dev - security update	Nessus	Debian Local Security Checks	medium
209810	Photon OS 5.0: Unbound PHSA-2024-5.0-0389	Nessus	PhotonOS Local Security Checks	medium
209809	Photon OS 4.0: Unbound PHSA-2024-4.0-0707	Nessus	PhotonOS Local Security Checks	medium
209525	Ubuntu 14.04 LTS / 16.04 LTS / 18.04 LTS / 20.04 LTS / 22.04 LTS / 24.04 LTS / 24.10 : Unbound vulnerability (USN-7080-1)	Nessus	Ubuntu Local Security Checks	medium
209318	Fedora 39 : unbound (2024-2ba00c906c)	Nessus	Fedora Local Security Checks	medium
209201	SUSE SLED15 / SLES15 / openSUSE 15 Security Update : unbound (SUSE-SU-2024:3647-1)	Nessus	SuSE Local Security Checks	medium
209195	SUSE SLED15 / SLES15 / openSUSE 15 Security Update : unbound (SUSE-SU-2024:3646-1)	Nessus	SuSE Local Security Checks	medium
209144	Amazon Linux 2 : unbound (ALAS-2024-2650)	Nessus	Amazon Linux Local Security Checks	medium
209066	Amazon Linux 2 : unbound (ALASUNBOUND-1.17-2024-003)	Nessus	Amazon Linux Local Security Checks	medium
209064	Amazon Linux 2 : unbound (ALASUNBOUND-2024-003)	Nessus	Amazon Linux Local Security Checks	medium
208978	Amazon Linux 2023 : python3-unbound, unbound, unbound-anchor (ALAS2023-2024-719)	Nessus	Amazon Linux Local Security Checks	medium
208764	CBL Mariner 2.0 Security Update: unbound (CVE-2024-8508)	Nessus	MarinerOS Local Security Checks	medium
208232	FreeBSD : Unbound -- Denial of service attack (2368755b-83f6-11ef-8d2e-a04a5edf46d9)	Nessus	FreeBSD Local Security Checks	medium
208220	Fedora 40 : unbound (2024-c07e065747)	Nessus	Fedora Local Security Checks	medium

Detections

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CVE-2024-8508

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Tenable Plugins

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