Skip to content
Fencer Intel
high 8.6

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 6y ago modified 4mo 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

Is CVE-2020-24606 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

Check with Fencer

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, squid34
    affected: 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+36416a77
    fixed: 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_9.4
    fixed: 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, 2026-11-09).

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

References

Sources

Fencer Intel 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.