High severity · published Nov 6, 2023
CVE-2023-46728
Squid is a caching proxy for the Web supporting HTTP, HTTPS, FTP, and more
7.5
CVSS
6%
EPSS
No
On KEV
Description
Squid is a caching proxy for the Web supporting HTTP, HTTPS, FTP, and more. Due to a NULL pointer dereference bug Squid is vulnerable to a Denial of Service attack against Squid's Gopher gateway. The gopher protocol is always available and enabled in Squid prior to Squid 6.0.1. Responses triggering this bug are possible to be received from any gopher server, even those without malicious intent. Gopher support has been removed in Squid version 6.0.1. Users are advised to upgrade. Users unable to upgrade should reject all gopher URL requests.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)6.0% · higher than 93% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
SQ
Squid · Squid-cache
before 6.0.1 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2023-46728
CVE.org
https://www.cve.org/CVERecord?id=CVE-2023-46728
Patch
https://github.com/squid-cache/squid/commit/6ea12e8fb590ac6959e9356a81aa3370576568c3
Vendor Advisory
https://github.com/squid-cache/squid/security/advisories/GHSA-cg5h-v6vc-w33f
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/A5QASTMCUSUEW3UOMKHZJB3FTONWSRXS/
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/MEV66D3PAAY6K7TWDT3WZBLCPLASFJDC/
security.netapp.com
https://security.netapp.com/advisory/ntap-20231214-0006/
lists.debian.org
https://lists.debian.org/debian-lts-announce/2025/09/msg00027.html
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