Bug 2316321 (CVE-2024-8508)

Summary: CVE-2024-8508 unbound: Unbounded name compression could lead to Denial of Service
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: asoldano, bbaranow, bdettelb, bmaxwell, brian.stansberry, cdewolf, chazlett, darran.lofthouse, dhanak, dkreling, doconnor, dosoudil, ecerquei, eglynn, fjuma, fmariani, fmongiar, gmalinko, ibek, istudens, ivassile, iweiss, janstey, jcantril, jjoyce, jnethert, jpoth, jrokos, jschluet, kverlaen, lgao, lhh, lsurette, lsvaty, mburns, mgarciac, michal.skrivanek, mnovotny, mosmerov, mperina, msochure, msvehla, nwallace, pemensik, pgrist, pjindal, pmackay, rguimara, rstancel, rstepani, sbonazzo, smaestri, tcunning, teagle, tom.jenkinson, yfang
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
URL: https://nlnetlabs.nl/downloads/unbound/CVE-2024-8508.txt
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Doc Text:
A flaw was found in Unbound which can lead to degraded performance and an eventual denial of service when handling replies with very large RRsets that require name compression to be applied. Versions prior to 1.21.1 do not have a hard limit on the number of name compression calculations that Unbound can perform per packet, meaning that if a specially crafted query is passed for the contents of a malicious zone with very large RRsets, Unbound may spend a considerable amount of time applying name compression to downstream replies, locking the CPU until the whole packet has been processed.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On: 2316358, 2316359    
Bug Blocks:    

Description OSIDB Bzimport 2024-10-03 17:01:16 UTC
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.

Comment 2 Petr Menšík 2024-11-13 14:23:02 UTC
Upstream information about the CVE:
https://nlnetlabs.nl/downloads/unbound/CVE-2024-8508.txt

Comment 3 errata-xmlrpc 2024-12-17 12:08:06 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9

Via RHSA-2024:11232 https://access.redhat.com/errata/RHSA-2024:11232

Comment 4 errata-xmlrpc 2024-12-17 18:47:10 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.4 Extended Update Support

Via RHSA-2024:11170 https://access.redhat.com/errata/RHSA-2024:11170

Comment 5 errata-xmlrpc 2025-01-15 00:51:16 UTC
This issue has been addressed in the following products:

  Red Hat OpenShift Container Platform 4.16

Via RHSA-2025:0140 https://access.redhat.com/errata/RHSA-2025:0140

Comment 6 errata-xmlrpc 2025-01-30 12:53:35 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2025:0837 https://access.redhat.com/errata/RHSA-2025:0837

Comment 7 errata-xmlrpc 2025-02-11 11:31:27 UTC
This issue has been addressed in the following products:

  Red Hat OpenShift Container Platform 4.17

Via RHSA-2025:1120 https://access.redhat.com/errata/RHSA-2025:1120

Comment 10 errata-xmlrpc 2025-05-20 17:25:54 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 10

Via RHSA-2025:8047 https://access.redhat.com/errata/RHSA-2025:8047

Comment 11 errata-xmlrpc 2025-05-27 11:42:16 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9

Via RHSA-2025:8197 https://access.redhat.com/errata/RHSA-2025:8197