Bug 2453345 (CVE-2026-27854)

Summary: CVE-2026-27854 DNSdist: DNSdist: Denial of Service due to use-after-free vulnerability in Lua
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedKeywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in DNSdist. An attacker could exploit this by sending crafted DNS queries that interact with the DNSQuestion:getEDNSOptions method in custom Lua code. This interaction can trigger a use-after-free vulnerability, potentially leading to a crash and a denial of service (DoS) for the DNSdist service.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Bug Depends On: 2453418, 2453419    
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Description OSIDB Bzimport 2026-03-31 13:02:06 UTC
An attacker might be able to trigger a use-after-free by sending crafted DNS queries to a DNSdist using the DNSQuestion:getEDNSOptions method in custom Lua code. In some cases DNSQuestion:getEDNSOptions might refer to a version of the DNS packet that has been modified, thus triggering a use-after-free and potentially a crash resulting in denial of service.