Bug 2445242 (CVE-2026-26018)

Summary: CVE-2026-26018 github.com/coredns/coredns: CoreDNS: Denial of Service vulnerability due to predictable pseudo-random number generation
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: unspecifiedCC: alcohan, gparvin, jbalunas, pahickey, rhaigner
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in CoreDNS, a DNS server that chains plugins. A remote attacker can exploit this flaw by sending specially crafted DNS queries. This vulnerability exists in CoreDNS's loop detection plugin due to the use of a predictable pseudo-random number generator (PRNG) for generating a secret query name. Successful exploitation can lead to a denial of service (DoS) by crashing the DNS server.
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Description OSIDB Bzimport 2026-03-06 16:02:01 UTC
CoreDNS is a DNS server that chains plugins. Prior to version 1.14.2, a denial of service vulnerability exists in CoreDNS's loop detection plugin that allows an attacker to crash the DNS server by sending specially crafted DNS queries. The vulnerability stems from the use of a predictable pseudo-random number generator (PRNG) for generating a secret query name, combined with a fatal error handler that terminates the entire process. This issue has been patched in version 1.14.2.