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TI-2021-21496 Aliases CVE-2021-46784

In Squid 3.x through 3.5.28, 4.x through 4.17, and 5.x before 5.6, due to improper buffer…

Priority LOW 37CWE-617Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Partial Red Hat: 9 fixed, 1 without a fix

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-617.

Summary

In Squid 3.x through 3.5.28, 4.x through 4.17, and 5.x before 5.6, due to improper buffer management, a Denial of Service can occur when processing long Gopher server responses.

Why it matters now

EPSS 0.05125 92nd percentileScored 2026-11-07
Fix Partial Red Hat: 6 advisoriesRed Hat: 9 fixed, 1 without a fix

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
——all versions—No fix listedCNA
  • — Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 4

CPEVersionsRoleVendor
cpe:2.3:a:squid-cache:squid:*:*:*:*:*:*:*:*3.0 – 3.5.28; 4.0 – 4.17; 5.0 to before 5.6Vulnerablesquid-cache
cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*10.0VulnerableDebian
cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*11.0VulnerableDebian
cpe:2.3:o:debian:debian_linux:12.0:*:*:*:*:*:*:*12.0VulnerableDebian
  • cpe:2.3:a:squid-cache:squid:*:*:*:*:*:*:*:* Versions 3.0 – 3.5.28; 4.0 – 4.17; 5.0 to before 5.6 Vulnerable ·squid-cache
  • cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:* Versions 10.0 Vulnerable ·Debian
  • cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:* Versions 11.0 Vulnerable ·Debian
  • cpe:2.3:o:debian:debian_linux:12.0:*:*:*:*:*:*:* Versions 12.0 Vulnerable ·Debian

Remediation

Red Hat 6 advisories

  • RHSA-2022:5542 Released 2022-07-11 · Red Hat rating Important
    squid security update
    • Red Hat Enterprise Linux Server (v. 7) squid-7:3.5.20-17.el7_9.7, squid-migration-script-7:3.5.20-17.el7_9.7
    • Red Hat Enterprise Linux Server Optional (v. 7) squid-sysvinit-7:3.5.20-17.el7_9.7
    • Red Hat Enterprise Linux Workstation (v. 7) squid-7:3.5.20-17.el7_9.7, squid-migration-script-7:3.5.20-17.el7_9.7
    • Red Hat Enterprise Linux Workstation Optional (v. 7) squid-sysvinit-7:3.5.20-17.el7_9.7
  • RHSA-2022:5526 Released 2022-07-07 · Red Hat rating Important
    squid:4 security update
    • Red Hat Enterprise Linux AppStream (v. 8) libecap-1.0.1-2.module+el8.1.0+4044+36416a77.aarch64::squid:4, libecap-1.0.1-2.module+el8.1.0+4044+36416a77.ppc64le::squid:4, libecap-1.0.1-2.module+el8.1.0+4044+36416a77.s390x::squid:4 +11
  • RHSA-2022:5528 Released 2022-07-07 · Red Hat rating Important
    squid:4 security update
    • Red Hat Enterprise Linux AppStream EUS (v.8.4) libecap-1.0.1-2.module+el8.1.0+4044+36416a77.aarch64::squid:4, libecap-1.0.1-2.module+el8.1.0+4044+36416a77.ppc64le::squid:4, libecap-1.0.1-2.module+el8.1.0+4044+36416a77.s390x::squid:4 +11
Show 3 more Red Hat advisories
  • RHSA-2022:5529 Released 2022-07-07 · Red Hat rating Important
    squid:4 security update
    • Red Hat Enterprise Linux AppStream EUS (v. 8.2) libecap-1.0.1-2.module+el8.1.0+4044+36416a77.aarch64::squid:4, libecap-1.0.1-2.module+el8.1.0+4044+36416a77.ppc64le::squid:4, libecap-1.0.1-2.module+el8.1.0+4044+36416a77.s390x::squid:4 +11
  • RHSA-2022:5527 Released 2022-07-07 · Red Hat rating Important
    squid security update
    • Red Hat Enterprise Linux AppStream (v. 9) squid-7:5.2-1.el9_0.1
  • RHSA-2022:5530 Released 2022-07-07 · Red Hat rating Important
    squid:4 security update
    • Red Hat Enterprise Linux AppStream E4S (v. 8.1) libecap-1.0.1-2.module+el8.1.0+4044+36416a77.ppc64le::squid:4, libecap-1.0.1-2.module+el8.1.0+4044+36416a77.src::squid:4, libecap-1.0.1-2.module+el8.1.0+4044+36416a77.x86_64::squid:4 +5

Vendor assessments

Red Hat

Red Hat rating: Important. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 6AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux AppStream (v. 8)Fixed RHSA-2022:5526
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2022:5527
Red Hat Enterprise Linux AppStream E4S (v. 8.1)Fixed RHSA-2022:5530
Red Hat Enterprise Linux AppStream EUS (v. 8.2)Fixed RHSA-2022:5529
Red Hat Enterprise Linux AppStream EUS (v.8.4)Fixed RHSA-2022:5528
Red Hat Enterprise Linux Server (v. 7)Fixed RHSA-2022:5542
Red Hat Enterprise Linux Server Optional (v. 7)Fixed RHSA-2022:5542
Red Hat Enterprise Linux Workstation (v. 7)Fixed RHSA-2022:5542
Red Hat Enterprise Linux Workstation Optional (v. 7)Fixed RHSA-2022:5542

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-46784

References

Patch 3

Advisory 2

Other 4

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences