Medium severity · published May 27, 2021
CVE-2021-28662
An issue was discovered in Squid 4.x before 4.15 and 5.x before 5.0.6
6.5
CVSS
71.8%
EPSS
No
On KEV
Description
An issue was discovered in Squid 4.x before 4.15 and 5.x before 5.0.6. If a remote server sends a certain response header over HTTP or HTTPS, there is a denial of service. This header can plausibly occur in benign network traffic.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)71.8% · higher than 99% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DL
Debian Linux · Debian
10.0 · source: NVD
FE
Fedora · Fedoraproject
33; 34 · source: NVD
SQ
Squid · Squid-cache
4.0.1 before 4.15; 5.0 before 5.0.6 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-28662
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-28662
Mailing List
http://seclists.org/fulldisclosure/2023/Oct/14
Mailing List
http://www.openwall.com/lists/oss-security/2023/10/11/3
Patch
http://www.squid-cache.org/Versions/v6/changesets/squid-6-051824924c709bd6162a378f746fb859454c674e.patch
Patch
https://github.com/squid-cache/squid/commit/051824924c709bd6162a378f746fb859454c674e
Patch
https://github.com/squid-cache/squid/security/advisories/GHSA-jjq6-mh2h-g39h
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/LSQ3U54ZCNXR44QRPW3AV2VCS6K3TKCF/
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