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TI-2024-16845 Aliases CVE-2024-25617

Denial of Service in HTTP Header parser in squid proxy

Priority HIGH 81CWE-182Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Partial Red Hat: 16 fixed, 1 without a fix

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-400.

Summary

Squid is an open source caching proxy for the Web supporting HTTP, HTTPS, FTP, and more. Due to a Collapse of Data into Unsafe Value bug ,Squid may be vulnerable to a Denial of Service attack against HTTP header parsing. This problem allows a remote client or a remote server to perform Denial of Service when sending oversized headers in HTTP messages. In versions of Squid prior to 6.5 this can be achieved if the request_header_max_size or reply_header_max_size settings are unchanged from the default. In Squid version 6.5 and later, the default setting of these parameters is safe. Squid will emit a critical warning in cache.log if the administrator is setting these parameters to unsafe values. Squid will not at this time prevent these settings from being changed to unsafe values. Users are advised to upgrade to version 6.5. There are no known workarounds for this vulnerability. This issue is also tracked as SQUID-2024:2

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.88094 99th percentileScored 2026-11-07
Fix Partial squid (squid-cache): 6.5Red Hat: 9 advisoriesRed Hat: 16 fixed, 1 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
squid-cachesquidbefore 6.56.5Patch availableCNA
  • squid Vendorsquid-cache Affected before 6.5 Fixed in 6.5 Patch available CNA

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:a:squid-cache:squid:*:*:*:*:*:*:*:*3.0 to before 6.5Vulnerablesquid-cache
cpe:2.3:a:netapp:bluexp:-:*:*:*:*:*:*:*not specified by NVDVulnerableNetApp
  • cpe:2.3:a:squid-cache:squid:*:*:*:*:*:*:*:* Versions 3.0 to before 6.5 Vulnerable ·squid-cache
  • cpe:2.3:a:netapp:bluexp:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NetApp

Remediation

  • Fix · CNA squid (squid-cache) Fixed in 6.5

Red Hat 9 advisories

  • RHSA-2024:2777 Released 2024-05-09 · Red Hat rating Important
    squid:4 security update
    • Red Hat Enterprise Linux AppStream AUS (v. 8.2) 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, libecap-devel-1.0.1-2.module+el8.1.0+4044+36416a77.x86_64::squid:4 +2
    • Red Hat Enterprise Linux AppStream E4S (v. 8.2) 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
    • Red Hat Enterprise Linux AppStream TUS (v. 8.2) 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, libecap-devel-1.0.1-2.module+el8.1.0+4044+36416a77.x86_64::squid:4 +2
  • RHSA-2024:1833 Released 2024-04-16 · Red Hat rating Important
    squid security update
    • Red Hat Enterprise Linux AppStream EUS (v.9.0) squid-7:5.2-1.el9_0.6
  • RHSA-2024:1832 Released 2024-04-16 · Red Hat rating Important
    squid:4 security update
    • Red Hat Enterprise Linux AppStream AUS (v.8.4) 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, libecap-devel-1.0.1-2.module+el8.1.0+4044+36416a77.x86_64::squid:4 +2
    • Red Hat Enterprise Linux AppStream E4S (v.8.4) 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.src::squid:4, libecap-1.0.1-2.module+el8.1.0+4044+36416a77.x86_64::squid:4 +5
    • Red Hat Enterprise Linux AppStream TUS (v.8.4) 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, libecap-devel-1.0.1-2.module+el8.1.0+4044+36416a77.x86_64::squid:4 +2
Show 6 more Red Hat advisories
  • RHSA-2024:1787 Released 2024-04-11 · Red Hat rating Important
    squid security update
    • Red Hat Enterprise Linux Server (v. 7) squid-7:3.5.20-17.el7_9.10, squid-migration-script-7:3.5.20-17.el7_9.10
    • Red Hat Enterprise Linux Server Optional (v. 7) squid-sysvinit-7:3.5.20-17.el7_9.10
    • Red Hat Enterprise Linux Workstation (v. 7) squid-7:3.5.20-17.el7_9.10, squid-migration-script-7:3.5.20-17.el7_9.10
    • Red Hat Enterprise Linux Workstation Optional (v. 7) squid-sysvinit-7:3.5.20-17.el7_9.10
  • RHSA-2024:1375 Released 2024-03-19 · Red Hat rating Important
    squid:4 security update
    • Red Hat Enterprise Linux AppStream (v. 8) libecap-1.0.1-2.module+el8.9.0+19703+a1da7223.aarch64::squid:4, libecap-1.0.1-2.module+el8.9.0+19703+a1da7223.ppc64le::squid:4, libecap-1.0.1-2.module+el8.9.0+19703+a1da7223.s390x::squid:4 +11
  • RHSA-2024:1376 Released 2024-03-19 · Red Hat rating Important
    squid security update
    • Red Hat Enterprise Linux AppStream (v. 9) squid-7:5.5-6.el9_3.8
  • RHSA-2024:1184 Released 2024-03-06 · Red Hat rating Important
    squid security update
    • Red Hat Enterprise Linux AppStream EUS (v.9.2) squid-7:5.5-5.el9_2.5
  • RHSA-2024:1066 Released 2024-03-04 · Red Hat rating Important
    squid:4 security update
    • Red Hat Enterprise Linux AppStream EUS (v.8.6) 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-2024:1062 Released 2024-03-01 · Red Hat rating Important
    squid:4 security update
    • Red Hat Enterprise Linux AppStream EUS (v.8.8) 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

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-2024:1375
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2024:1376
Red Hat Enterprise Linux AppStream AUS (v. 8.2)Fixed RHSA-2024:2777
Red Hat Enterprise Linux AppStream AUS (v.8.4)Fixed RHSA-2024:1832
Red Hat Enterprise Linux AppStream E4S (v. 8.2)Fixed RHSA-2024:2777
Red Hat Enterprise Linux AppStream E4S (v.8.4)Fixed RHSA-2024:1832
Red Hat Enterprise Linux AppStream EUS (v.8.6)Fixed RHSA-2024:1066
Red Hat Enterprise Linux AppStream EUS (v.8.8)Fixed RHSA-2024:1062
Red Hat Enterprise Linux AppStream EUS (v.9.0)Fixed RHSA-2024:1833
Red Hat Enterprise Linux AppStream EUS (v.9.2)Fixed RHSA-2024:1184
Red Hat Enterprise Linux AppStream TUS (v. 8.2)Fixed RHSA-2024:2777
Red Hat Enterprise Linux AppStream TUS (v.8.4)Fixed RHSA-2024:1832
Red Hat Enterprise Linux Server (v. 7)Fixed RHSA-2024:1787
Red Hat Enterprise Linux Server Optional (v. 7)Fixed RHSA-2024:1787
Red Hat Enterprise Linux Workstation (v. 7)Fixed RHSA-2024:1787
Red Hat Enterprise Linux Workstation Optional (v. 7)Fixed RHSA-2024:1787

Timeline

  1. 2026-10-02 Threatist record created from CVE-2024-25617

References

Patch 2

Advisory 1

  • TI-2025-38486 Squid vulnerable to information disclosure via authentication credential leakage in error handling CVSS 3.1CRITICAL 10.0
  • TI-2024-16566 SQUID-2024:1 Denial of Service in HTTP Chunked Decoding CVSS 3.1HIGH 8.6
  • TI-2023-26921 Denial of Service in HTTP Message Processing in Squid CVSS 3.1HIGH 8.6
  • TI-2023-27496 SQUID-2023:10 Denial of Service in HTTP Request parsing CVSS 3.1HIGH 8.6
  • TI-2023-25306 Squid: denial of service in http digest authentication CVSS 3.1HIGH 8.6
  • TI-2016-03919 client_side.cc in Squid before 3.5.18 and 4.x before 4.0.10 does not properly ignore the… CVSS 3.0HIGH 8.6
See all 110 →

Sources

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