Medium severity · published May 27, 2021
CVE-2021-28652
An issue was discovered in Squid before 4.15 and 5.x before 5.0.6
4.9
CVSS
4.3%
EPSS
No
On KEV
Description
An issue was discovered in Squid before 4.15 and 5.x before 5.0.6. Due to incorrect parser validation, it allows a Denial of Service attack against the Cache Manager API. This allows a trusted client to trigger memory leaks that. over time, lead to a Denial of Service via an unspecified short query string. This attack is limited to clients with Cache Manager API access privilege.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
High
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)4.3% · higher than 91% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DL
Debian Linux · Debian
9.0; 10.0 · source: NVD
FE
Fedora · Fedoraproject
33; 34 · source: NVD
SQ
Squid · Squid-cache
1.0 before 4.15; 5.0 before 5.0.6 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-28652
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-28652
Mailing List
http://seclists.org/fulldisclosure/2023/Oct/14
Mailing List
http://www.openwall.com/lists/oss-security/2023/10/11/3
Exploit
https://bugs.squid-cache.org/show_bug.cgi?id=5106
Patch
https://github.com/squid-cache/squid/security/advisories/GHSA-m47m-9hvw-7447
Mailing List
https://lists.debian.org/debian-lts-announce/2021/06/msg00014.html
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/LSQ3U54ZCNXR44QRPW3AV2VCS6K3TKCF/
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