CVE-2020-15810 - CVE House
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Status published Medium CVE-2020-15810

An issue was discovered in Squid before 4.13 and 5.x...

Vulnerability Description

An issue was discovered in Squid before 4.13 and 5.x before 5.0.4. Due to incorrect data validation, HTTP Request Smuggling attacks may succeed against HTTP and HTTPS traffic. This leads to cache poisoning. This allows any client, including browser scripts, to bypass local security and poison the proxy cache and any downstream caches with content from an arbitrary source. When configured for relaxed header parsing (the default), Squid relays headers containing whitespace characters to upstream servers. When this occurs as a prefix to a Content-Length header, the frame length specified will be ignored by Squid (allowing for a conflicting length to be used from another Content-Length header) but relayed upstream.

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

View all reports →

Affected Software

squid, ubuntu linux, debian linux, fedora, leap
Vulnerable Versions:
0, 5.0, 16.04, 18.04, 20.04, 9.0, 10.0, 31, 32, 33, 15.1, 15.2

Timeline

Official Publish: September 2nd, 2020
Last Modified: August 4th, 2024
Added to House: July 21st, 2026

CVSS Vectors

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

Weaknesses (CWE)

No CWE data available

MITRE ATT&CK TTPs

No associated TTPs found for this vulnerability.