CVE-2023-50269

SQUID-2023:10 Denial of Service in HTTP Request parsing

HIGH
7.5
CVSS Score
Published: December 14, 2023 at 05:09 PM UTC
Updated: June 17, 2026 at 06:39 AM UTC
2 products affected across 1 vendorCache SquidSquid

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Severity
HIGH7.5
Exploit prediction
EPSS 58%
SSVC
No known exploit

Description

Squid is a caching proxy for the Web. Due to an Uncontrolled Recursion bug in versions 2.6 through 2.7.STABLE9, versions 3.1 through 5.9, and versions 6.0.1 through 6.5, Squid may be vulnerable to a Denial of Service attack against HTTP Request parsing. This problem allows a remote client to perform Denial of Service attack by sending a large X-Forwarded-For header when the follow_x_forwarded_for feature is configured. This bug is fixed by Squid version 6.6. In addition, patches addressing this problem for the stable releases can be found in Squid's patch archives.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v ≤ 2.7.STABLE9v ≤ 5.9v < 6.63.1 ≤ v ≤ 5.96.0.1 ≤ v ≤ 6.52.62.72.7 stable12.7 stable22.7 stable32.7 stable42.7 stable52.7 stable62.7 stable72.7 stable82.7 stable9
Affected range stops below 6.6, so it looks safe — our inference, not a vendor statement
v ≤ 2.7.STABLE9v ≤ 5.9v < 6.6
Affected range stops below 6.6, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.

SSVC — Action Prioritization

SSVCNo known exploitAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-674

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