Medium severity · published Apr 15, 2020
CVE-2019-12522
An issue was discovered in Squid through 4.7
4.5
CVSS
0.3%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L
Attack vector
Local
Complexity
High
Privileges
Low
User interaction
None
Confidentiality
Low
Integrity
Low
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 28% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
SQ
Squid · Squid-cache
through 4.7 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2019-12522
CVE.org
https://www.cve.org/CVERecord?id=CVE-2019-12522
Third Party Advisory
https://gitlab.com/jeriko.one/security/-/blob/master/squid/CVEs/CVE-2019-12522.txt
Third Party Advisory
https://security.netapp.com/advisory/ntap-20210205-0006/
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