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TI-2016-03920 Aliases CVE-2016-4554GHSA-p847-vwj5-4q73

mime_header.cc in Squid before 3.5.18 allows remote attackers to bypass intended…

Priority MEDIUM 64CWE-345Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
None · High · None
Fix status
Partial Red Hat: 6 fixed, 1 without a fix

Attack profile from CVSS 3.0 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-345.

Summary

mime_header.cc in Squid before 3.5.18 allows remote attackers to bypass intended same-origin restrictions and possibly conduct cache-poisoning attacks via a crafted HTTP Host header, aka a "header smuggling" issue.

Why it matters now

EPSS 0.38893 98th percentileScored 2026-11-07
Fix Partial Red Hat: 3 advisoriesRed Hat: 6 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 · 7

CPEVersionsRoleVendor
cpe:2.3:o:oracle:linux:6:*:*:*:*:*:*:*6VulnerableOracle
cpe:2.3:o:oracle:linux:7:*:*:*:*:*:*:*7VulnerableOracle
cpe:2.3:a:squid-cache:squid:*:*:*:*:*:*:*:*up to 3.5.17Vulnerablesquid-cache
cpe:2.3:o:canonical:ubuntu_linux:12.04:*:*:*:lts:*:*:*12.04VulnerableCanonical
cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:lts:*:*:*14.04VulnerableCanonical
cpe:2.3:o:canonical:ubuntu_linux:15.10:*:*:*:*:*:*:*15.10VulnerableCanonical
cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:*16.04VulnerableCanonical
  • cpe:2.3:o:oracle:linux:6:*:*:*:*:*:*:* Versions 6 Vulnerable ·Oracle
  • cpe:2.3:o:oracle:linux:7:*:*:*:*:*:*:* Versions 7 Vulnerable ·Oracle
  • cpe:2.3:a:squid-cache:squid:*:*:*:*:*:*:*:* Versions up to 3.5.17 Vulnerable ·squid-cache
  • cpe:2.3:o:canonical:ubuntu_linux:12.04:*:*:*:lts:*:*:* Versions 12.04 Vulnerable ·Canonical
  • cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:lts:*:*:* Versions 14.04 Vulnerable ·Canonical
  • cpe:2.3:o:canonical:ubuntu_linux:15.10:*:*:*:*:*:*:* Versions 15.10 Vulnerable ·Canonical
  • cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:* Versions 16.04 Vulnerable ·Canonical

Remediation

Red Hat 3 advisories

  • RHSA-2016:1138 Released 2016-05-31 · Red Hat rating Moderate
    squid security update
    • Red Hat Enterprise Linux Server (v. 6) squid-7:3.1.23-16.el6_8.4
    • Red Hat Enterprise Linux Workstation (v. 6) squid-7:3.1.23-16.el6_8.4
  • RHSA-2016:1140 Released 2016-05-31 · Red Hat rating Moderate
    squid34 security update
    • Red Hat Enterprise Linux Server (v. 6) squid34-7:3.4.14-9.el6_8.3
    • Red Hat Enterprise Linux Workstation (v. 6) squid34-7:3.4.14-9.el6_8.3
  • RHSA-2016:1139 Released 2016-05-31 · Red Hat rating Moderate
    squid security update
    • Red Hat Enterprise Linux Server (v. 7) squid-7:3.3.8-26.el7_2.3
    • Red Hat Enterprise Linux Server Optional (v. 7) squid-sysvinit-7:3.3.8-26.el7_2.3
    • Red Hat Enterprise Linux Workstation (v. 7) squid-7:3.3.8-26.el7_2.3
    • Red Hat Enterprise Linux Workstation Optional (v. 7) squid-sysvinit-7:3.3.8-26.el7_2.3

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat Enterprise Linux 5AffectedNo fix planned: Will not fix
Red Hat Enterprise Linux Server (v. 6)Fixed RHSA-2016:1138, RHSA-2016:1140
Red Hat Enterprise Linux Server (v. 7)Fixed RHSA-2016:1139
Red Hat Enterprise Linux Server Optional (v. 7)Fixed RHSA-2016:1139
Red Hat Enterprise Linux Workstation (v. 6)Fixed RHSA-2016:1138, RHSA-2016:1140
Red Hat Enterprise Linux Workstation (v. 7)Fixed RHSA-2016:1139
Red Hat Enterprise Linux Workstation Optional (v. 7)Fixed RHSA-2016:1139

Timeline

  1. 2026-10-02 Threatist record created from CVE-2016-4554
  2. 2026-10-03 Alias added: GHSA-p847-vwj5-4q73

References

Patch 5

Advisory 11

Sources

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