Privilege escalation in Squid-Cache Squid
CVE-2019-12522
An issue was discovered in Squid through 4.7. When Squid is run as root, it spawns its child processes as a lesser user, by default the user nobody. This is done via the leave_suid call. leave_suid leaves the Saved UID as 0. This makes it trivial for an attacker who has compromised the child process to escalate their privileges back to root.
Vulnerability class: Privilege Escalation
EPSS: 0.003 (27.0th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 4.5 (Medium). Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L.
Affected products
- Squid-cache Squid
- N/a — versions n/a
Weakness classification (CWE)
References
- cve@mitre.org (Third Party Advisory, x_refsource_MISC)
- cve@mitre.org (x_refsource_CONFIRM, Third Party Advisory)
Frequently asked questions
- What is CVE-2019-12522?
- CVE-2019-12522 is a medium-severity vulnerability in Squid-Cache Squid, classified under Improper Privilege Management. CVSS score: 4.5/10. Published 2020-04-15.
- How severe is CVE-2019-12522?
- Medium severity. CVSS v3 base score is 4.5 out of 10.