Bug 2451577 (CVE-2026-32748)

Summary: CVE-2026-32748 Squid: Squid: Denial of Service via crafted ICP traffic
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: unspecifiedKeywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in Squid. A remote attacker can exploit this vulnerability by sending specially crafted ICP (Internet Cache Protocol) traffic. This can lead to a Denial of Service (DoS) due to premature resource release and use-after-free vulnerabilities. This attack is possible in Squid deployments with explicitly enabled ICP support.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Bug Depends On: 2451600, 2451601    
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Description OSIDB Bzimport 2026-03-26 01:01:54 UTC
Squid is a caching proxy for the Web. Prior to version 7.5, due to premature release of resource during expected lifetime and heap Use-After-Free bugs, Squid is vulnerable to Denial of Service when handling ICP traffic. This problem allows a remote attacker to perform a reliable and repeatable Denial of Service attack against the Squid service using ICP protocol. This attack is limited to Squid deployments that explicitly enable ICP support (i.e. configure non-zero `icp_port`). This problem _cannot_ be mitigated by denying ICP queries using `icp_access` rules. This bug is fixed in Squid version 7.5.

Comment 2 errata-xmlrpc 2026-03-31 20:03:44 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9

Via RHSA-2026:6301 https://access.redhat.com/errata/RHSA-2026:6301