CVE-2016-4053

CVE-2016-4053 is a low-severity vulnerability in Squid-cache Squid with a CVSS 3.x base score of 3.7. Its EPSS exploit-prediction score of 14% places it in the 96th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-119.

Key facts

• Severity: Low (CVSS 3.x base score 3.7)
• CVSS v2: 4.3
• EPSS exploit prediction: 14% (96th percentile)
• Actively exploited: Not listed in CISA KEV
• Weakness: CWE-119
• Affected product: Squid-cache Squid
• Published: 2016-04-25
• Last modified: 2026-06-17

Description

Squid 3.x before 3.5.17 and 4.x before 4.0.9 allow remote attackers to obtain sensitive stack layout information via crafted Edge Side Includes (ESI) responses, related to incorrect use of assert and compiler optimization.

Frequently asked questions

What is CVE-2016-4053?

Squid 3.x before 3.5.17 and 4.x before 4.0.9 allow remote attackers to obtain sensitive stack layout information via crafted Edge Side Includes (ESI) responses, related to incorrect use of assert and compiler optimization.

How severe is CVE-2016-4053?

CVE-2016-4053 has a CVSS 3.x base score of 3.7, rated low severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.

Is CVE-2016-4053 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 14% (96th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2016-4053?

CVE-2016-4053 primarily affects Squid-cache Squid. In total, 146 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2016-4053?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2016-4053 published?

CVE-2016-4053 was published on 2016-04-25 and last updated on 2026-06-17.

References

• http://lists.opensuse.org/opensuse-security-announce/2016-08/msg00010.html
• http://lists.opensuse.org/opensuse-security-announce/2016-08/msg00040.html
• http://lists.opensuse.org/opensuse-updates/2016-08/msg00069.html
• http://www.debian.org/security/2016/dsa-3625
• http://www.openwall.com/lists/oss-security/2016/04/20/6
• http://www.openwall.com/lists/oss-security/2016/04/20/9
• http://www.oracle.com/technetwork/security-advisory/cpujul2016-2881720.html
• http://www.oracle.com/technetwork/topics/security/linuxbulletinapr2016-2952096.html
• http://www.securityfocus.com/bid/86788
• http://www.securityfocus.com/bid/91787
• http://www.securitytracker.com/id/1035647
• http://www.squid-cache.org/Advisories/SQUID-2016_6.txt
• http://www.ubuntu.com/usn/USN-2995-1
• https://access.redhat.com/errata/RHSA-2016:1138
• https://access.redhat.com/errata/RHSA-2016:1139
• https://access.redhat.com/errata/RHSA-2016:1140
• https://security.gentoo.org/glsa/201607-01

Affected products (146)

• cpe:2.3:a:squid-cache:squid:3.0:*:*:*:*:*:*:*
• cpe:2.3:a:squid-cache:squid:3.1:*:*:*:*:*:*:*
• cpe:2.3:a:squid-cache:squid:3.1.0.1:*:*:*:*:*:*:*
• cpe:2.3:a:squid-cache:squid:3.1.0.2:*:*:*:*:*:*:*
• cpe:2.3:a:squid-cache:squid:3.1.0.3:*:*:*:*:*:*:*
• cpe:2.3:a:squid-cache:squid:3.1.0.4:*:*:*:*:*:*:*
• cpe:2.3:a:squid-cache:squid:3.1.0.5:*:*:*:*:*:*:*
• cpe:2.3:a:squid-cache:squid:3.1.0.6:*:*:*:*:*:*:*
• cpe:2.3:a:squid-cache:squid:3.1.0.7:*:*:*:*:*:*:*
• cpe:2.3:a:squid-cache:squid:3.1.0.8:*:*:*:*:*:*:*
• cpe:2.3:a:squid-cache:squid:3.1.0.9:*:*:*:*:*:*:*
• cpe:2.3:a:squid-cache:squid:3.1.0.10:*:*:*:*:*:*:*
• cpe:2.3:a:squid-cache:squid:3.1.0.11:*:*:*:*:*:*:*
• cpe:2.3:a:squid-cache:squid:3.1.0.12:*:*:*:*:*:*:*
• cpe:2.3:a:squid-cache:squid:3.1.0.13:*:*:*:*:*:*:*
• cpe:2.3:a:squid-cache:squid:3.1.0.14:*:*:*:*:*:*:*
• cpe:2.3:a:squid-cache:squid:3.1.0.15:*:*:*:*:*:*:*
• cpe:2.3:a:squid-cache:squid:3.1.0.16:*:*:*:*:*:*:*
• cpe:2.3:a:squid-cache:squid:3.1.0.17:*:*:*:*:*:*:*
• cpe:2.3:a:squid-cache:squid:3.1.0.18:*:*:*:*:*:*:*
• cpe:2.3:a:squid-cache:squid:3.1.1:*:*:*:*:*:*:*
• cpe:2.3:a:squid-cache:squid:3.1.2:*:*:*:*:*:*:*
• cpe:2.3:a:squid-cache:squid:3.1.3:*:*:*:*:*:*:*
• cpe:2.3:a:squid-cache:squid:3.1.4:*:*:*:*:*:*:*
• cpe:2.3:a:squid-cache:squid:3.1.5:*:*:*:*:*:*:*
• cpe:2.3:a:squid-cache:squid:3.1.5.1:*:*:*:*:*:*:*
• cpe:2.3:a:squid-cache:squid:3.1.6:*:*:*:*:*:*:*
• cpe:2.3:a:squid-cache:squid:3.1.7:*:*:*:*:*:*:*
• cpe:2.3:a:squid-cache:squid:3.1.8:*:*:*:*:*:*:*
• cpe:2.3:a:squid-cache:squid:3.1.9:*:*:*:*:*:*:*
• cpe:2.3:a:squid-cache:squid:3.1.10:*:*:*:*:*:*:*
• cpe:2.3:a:squid-cache:squid:3.1.11:*:*:*:*:*:*:*
• cpe:2.3:a:squid-cache:squid:3.1.12:*:*:*:*:*:*:*
• cpe:2.3:a:squid-cache:squid:3.1.12.1:*:*:*:*:*:*:*
• cpe:2.3:a:squid-cache:squid:3.1.12.2:*:*:*:*:*:*:*
• cpe:2.3:a:squid-cache:squid:3.1.12.3:*:*:*:*:*:*:*
• cpe:2.3:a:squid-cache:squid:3.1.13:*:*:*:*:*:*:*
• cpe:2.3:a:squid-cache:squid:3.1.14:*:*:*:*:*:*:*
• cpe:2.3:a:squid-cache:squid:3.1.15:*:*:*:*:*:*:*
• cpe:2.3:a:squid-cache:squid:3.1.16:*:*:*:*:*:*:*

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All CVEs affecting Squid-cache Squid →

Other CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer) vulnerabilities

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• CVE-2022-27625 — Critical (CVSS 10.0): A vulnerability regarding improper restriction of operations within the bounds of a memory buffer is found in the…
• CVE-2022-27624 — Critical (CVSS 10.0): A vulnerability regarding improper restriction of operations within the bounds of a memory buffer is found in the…
• CVE-2020-11896 — Critical (CVSS 10.0): The Treck TCP/IP stack before 6.0.1.66 allows Remote Code Execution, related to IPv4 tunneling.

Browse all CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer) vulnerabilities →

Threat intelligence

Threat-intel indicators referencing this CVE:

• 193.90.12.40 (ipv4-addr)
• 200.89.159.59 (ipv4-addr)