SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2020-15810

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.

MEDIUM 6.5EPSS 2.53%

Does this matter?

Lower severity and a low EPSS score (2.53%). Track it; it rarely justifies an emergency change on its own.

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.

CVSS 3.1
6.5 MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
EPSS
2.53% probability · 84th percentile
CISA KEV
Not listed
Weakness
CWE-444
Affected
squid-cache/squid · canonical/ubuntu linux · debian/debian linux · fedoraproject/fedora · opensuse/leap
Source
cve@mitre.org

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.