CVE-2019-18678 - CVE House
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Status published Medium CVE-2019-18678

An issue was discovered in Squid 3.x and 4.x through...

Vulnerability Description

An issue was discovered in Squid 3.x and 4.x through 4.8. It allows attackers to smuggle HTTP requests through frontend software to a Squid instance that splits the HTTP Request pipeline differently. The resulting Response messages corrupt caches (between a client and Squid) with attacker-controlled content at arbitrary URLs. Effects are isolated to software between the attacker client and Squid. There are no effects on Squid itself, nor on any upstream servers. The issue is related to a request header containing whitespace between a header name and a colon.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

No credits recorded in the NVD database.

References

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Affected Vendor

squid-cache

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Affected Software

squid, ubuntu linux, debian linux, fedora
Vulnerable Versions:
3.0, 4.0, 16.04, 18.04, 19.04, 19.10, 8.0, 30, 31

Timeline

Official Publish: November 26th, 2019
Last Modified: August 5th, 2024
Added to House: July 20th, 2026

CVSS Vectors

V3: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

Weaknesses (CWE)

No CWE data available

MITRE ATT&CK TTPs

No associated TTPs found for this vulnerability.