CVE-2020-24606 json
Squid before 4.13 and 5.x before 5.0.4 allows a trusted peer to perform Denial of Service by consuming all available CPU cycles during hand…
published 2020-08-24 6 y ago modified 2026-06-17 4 mo ago also EUVD-2020-17323
- cvss
- 8.6
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 4.6%
- EPSS 4.6% chance of exploitation in 30 days, percentile 91%
- public exploits
- 0
- none known
Summary
Squid before 4.13 and 5.x before 5.0.4 allows a trusted peer to perform Denial of Service by consuming all available CPU cycles during handling of a crafted Cache Digest response message. This only occurs when cache_peer is used with the cache digests feature. The problem exists because peerDigestHandleReply() livelocking in peer_digest.cc mishandles EOF.
Patch / fix
- squid-cache squid 4.13, 5.0.4
- squid Debian 14, Debian 13, Debian 12 4.13-1
debian advisories DEBIAN-CVE-2020-24606
- squid Ubuntu 20.04 LTS 4.10-1ubuntu1.2
- squid3 Ubuntu 16.04 LTS 3.5.12-1ubuntu7.15
- squid3 Ubuntu 18.04 LTS 3.5.27-1ubuntu1.9
ubuntu advisories UBUNTU-CVE-2020-24606
Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0
- squid RHEL 7 7:3.5.20-17.el7_9.4
- squid-sysvinit RHEL 7 7:3.5.20-17.el7_9.4
- squid-migration-script RHEL 7 7:3.5.20-17.el7_9.4
- squid RHEL 8 7:4.11-3.module+el8.3.0+7851+7808b5f9
- libecap RHEL 8 1.0.1-2.module+el8.1.0+4044+36416a77
red hat advisories RHSA-2020:4082RHSA-2020:4743
- squid3 SLES 11 SP4-LTSS, SLE Point of Sale 11 SP3 3.1.23-8.16.37.15.1
- squid SLES for SAP 12 SP4, SLES for SAP 12 SP3, SLES for SAP 12 SP2 +12 more 3.5.21-26.32.1
- squid SLES for SAP 12 SP5, SLES 12 SP5 4.13-4.15.1
- squid SLES for SAP 15, SLES 15-LTSS, SLE Module for Server Applications 15 SP2 +3 more 4.13-5.23.1
suse advisories SUSE-SU-2020:14590-1SUSE-SU-2020:2471-1SUSE-SU-2020:2443-1SUSE-SU-2020:2442-1
- squid openSUSE Tumbleweed 4.16-1.5
- squid openSUSE Leap 15.2 4.13-lp152.2.6.1
- squid openSUSE Leap 15.1 4.13-lp151.2.24.1
opensuse advisories openSUSE-SU-2024:11403-1openSUSE-SU-2020:1369-1openSUSE-SU-2020:1346-1
- libecap AlmaLinux 8 1.0.1-2.module_el8.6.0+2741+01592ae8
almalinux advisories ALSA-2020:4743
- libecap Rocky Linux 8 1.0.1-2.module+el8.4.0+404+316a0dc5
rocky linux advisories RLSA-2020:4743
- squid Alpine 3.12, Alpine 3.11, Alpine 3.10 +1 more 4.13-r0
- squid Alpine 3.24, Alpine 3.23, Alpine 3.22 +9 more 4.13.0-r0
alpine advisories ALPINE-CVE-2020-24606
Alpine secdb © Alpine Linux, from https://secdb.alpinelinux.org via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0
Vendor advisories
What the vendors themselves say about their products: affected, fixed or not affected, and what to do.
red hat product security vex CVE-2020-24606 updated cvss 7.5
squid: Improper input validation could result in a DoS
-
Red Hat Enterprise Linux 5 squid Red Hat Enterprise Linux 6 squid, squid34affected: workaround, no fix planned “Add the no-digest option to all cache_peer lines in squid.conf”
-
Red Hat Enterprise Linux AppStream (v. 8) squid 4.11-3.module+el8.3.0+7851+7808b5f9, libecap 1.0.1-2.module+el8.1.0+4044+36416a77fixed: vendor fix “Add the no-digest option to all cache_peer lines in squid.conf” RHSA-2020:4743
-
Red Hat Enterprise Linux Server (v. 7) squid 3.5.20-17.el7_9.4, squid-migration-script 3.5.20-17.el7_9.4 Red Hat Enterprise Linux Server Optional (v. 7) squid-sysvinit 3.5.20-17.el7_9.4 Red Hat Enterprise Linux Workstation (v. 7) squid 3.5.20-17.el7_9.4, squid-migration-script 3.5.20-17.el7_9.4 Red Hat Enterprise Linux Workstation Optional (v. 7) squid-sysvinit 3.5.20-17.el7_9.4fixed: vendor fix “Add the no-digest option to all cache_peer lines in squid.conf” RHSA-2020:4082
Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf
Exploit prediction
4.61% chance of exploitation in the next 30 days, higher than 91% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 8.6 | CVSS:3.1/AC:L/AV:N/A:H/C:N/I:N/PR:N/S:C/UI:N |
| CNA | 3.1 | 8.6 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H |
| NVD | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| NVD | 2.0 | 7.1 | AV:N/AC:M/Au:N/C:N/I:N/A:C |
Classification
- Weakness
-
- CWE-667 Improper Locking
References
-
squid-cache.org
/Versions/v4/changesets/SQUID-2020_9.patch
patch, vendor-advisory
-
debian.org
/security/2020/dsa-4751
vendor-advisory, third-party-advisory
-
usn.ubuntu.com
/4477-1/
vendor-advisory, third-party-advisory
-
lists.fedoraproject.org
/archives/list/package-announce%40lists.fedoraproject.org/message/HJJDI7JQFGQLVNCKMVY64LAFMKERAOK7/
vendor-advisory
-
lists.fedoraproject.org
/archives/list/package-announce%40lists.fedoraproject.org/message/BMTFLVB7GLRF2CKGFPZ4G4R5DIIPHWI3/
vendor-advisory
-
lists.opensuse.org
/opensuse-security-announce/2020-09/msg00012.html
vendor-advisory, mailing-list, third-party-advisory
-
lists.opensuse.org
/opensuse-security-announce/2020-09/msg00017.html
vendor-advisory, mailing-list, third-party-advisory
-
lists.fedoraproject.org
/archives/list/package-announce%40lists.fedoraproject.org/message/BE6FKUN7IGTIR2MEEMWYDT7N5EJJLZI2/
vendor-advisory
-
usn.ubuntu.com
/4551-1/
vendor-advisory, third-party-advisory
-
github.com
/squid-cache/squid/security/advisories/GHSA-vvj7-xjgq-g2jg
third-party-advisory
-
lists.debian.org
/debian-lts-announce/2020/10/msg00005.html
mailing-list, third-party-advisory
-
security.netapp.com
/advisory/ntap-20210219-0007/
third-party-advisory
-
security.netapp.com
/advisory/ntap-20210226-0007/
broken-link
-
security.netapp.com
/advisory/ntap-20210226-0006/
third-party-advisory
Sources
- CVE List CVE-2020-24606
- NVD CVE-2020-24606
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.