High (7.5) in squid-cache squid. EPSS 4.8% chance of exploitation in the next 30 days.
Incorrect HTTP Request header comparison in Squid HTTP Proxy 3.5.0.1 through 3.5.22, and 4.0.1 through 4.0.16 results in Collapsed Forwarding feature mistakenly identifying some private responses as being suitable for delivery to multiple clients.
Severity
CVSS 3.1
7.5 high
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
EPSS
4.8% chance of exploitation in the next 30 days; higher than 91% of CVEs (scores of 2026-10-31)