CVE-2023-49288
highpriority · track · 32EPSS 0.048 · 92 %ileDEEURUUSEPSS · scored 2026-10-27
Squid is a caching proxy for the Web supporting HTTP, HTTPS, FTP, and more. Affected versions of squid are subject to a a Use-After-Free bug which can lead to a Denial of Service attack via collapsed forwarding. All versions of Squid from 3.5 up to and including 5.9 configured with "collapsed_forwarding on" are vulnerable. Configurations with "collapsed_forwarding off" or without a "collapsed_forwarding" directive are not vulnerable. This bug is fixed by Squid version 6.0.1. Users are advised to upgrade. Users unable to upgrade should remove all collapsed_forwarding lines from their squid.conf.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.9–8.6
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (18)
Products and version ranges known to be affected.
advisories (2)
Vendor and ecosystem advisories describing this.
- WID-SEC-W-2023-3049Squid: Mehrere Schwachstellen ermöglichen Denial of ServiceDeutsch2023-12-03csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in Squid ausnutzen, um einen Denial of Service Angriff durchzuführen.
- WID-SEC-W-2024-1248Xerox FreeFlow Print Server: Mehrere SchwachstellenDeutsch2024-05-28csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Xerox FreeFlow Print Server ausnutzen, um die Vertraulichkeit, Verfügbarkeit und Integrität des Systems zu gefährden
also known as (3)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (12)
External citations — patches, advisories, analysis.
- https://access.redhat.com/security/cve/cve-2023-49288cnnvd
- https://github.com/squid-cache/squid/security/advisories/GHSA-rj5h-46j6-q2g5cnnvd
- https://nvd.nist.gov/vuln/detail/CVE-2023-49288cnnvd
- https://vigilance.fr/vulnerability/Squid-denial-of-service-via-HTTP-Collapsed-Forwarding-43012cnnvd
- https://github.com/squid-cache/squid/security/advisories/GHSA-rj5h-46j6-q2g5enisa_euvd
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/A5QASTMCUSUEW3UOMKHZJB3FTONWSRXS/enisa_euvd
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/MEV66D3PAAY6K7TWDT3WZBLCPLASFJDC/enisa_euvd
- https://security.netapp.com/advisory/ntap-20240119-0006/enisa_euvd
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