Skip to content
VulniPulse
Advisory severityMedium6.5Red Hat Linux

Medium [CVE-2026-47184] Denial of Service via uncontrolled memory growth

This medium-severity Red Hat Linux advisory covers CVE-2026-47184 affecting Red Hat OpenShift Container Platform 4, Red Hat OpenStack Platform 16.2, Red Hat OpenStack Platform 17.1.

Aggregated and source-linked by VulniPulse. Data sources, validation and limitations.

CVE-2026-47184 Source published Source updated

VulniPulse record published Record updated

Affected products & platforms
Red Hat LinuxUnclassified
Open source advisory

Android app · Google Play

Monitor future Red Hat Linux CVEs from your phone.

Choose a whole vendor or a precise platform, then receive matching security advisories by phone notification, email, or both. Coverage follows 32 official vendor sources and 160+ reviewed platform categories.

Matching phone alertsOptional email delivery

Summary

Zeroconf is a pure Python implementation of multicast DNS service discovery.

Prior to 0.149.7, DNSCache._async_add inserted every response record into cache, _expirations, _expire_heap, and service_cache without a cap, allowing unauthenticated hosts on the local link over UDP/5353 (224.0.0.251 / ff02::fb) to multicast valid mDNS responses with unique names and cause memory exhaustion, slower cache lookups, slower async_expire passes, and broken discovery, registration, and ServiceBrowser callbacks.

This issue is fixed in version 0.149.7. An unauthenticated attacker on the local network can send specially crafted multicast DNS responses.

This can lead to uncontrolled memory growth, causing memory exhaustion and significantly degrading the performance of the service, ultimately resulting in a denial of service (DoS). Exploitation requires the attacker to be on the same local link as the affected host, consistent with Red Hat's Adjacent (AV:A) attack vector scoring.

Red Hat's CVSS score matches the vendor/CVE.org assessment for this flaw. This flaw is one of a batch of related Zeroconf issues discovered and fixed close together (CVE-2026-47180, CVE-2026-47183, CVE-2026-47184, CVE-2026-48045, CVE-2026-48487); all affect the same Red Hat product streams in the same way and were triaged consistently as a batch.

Affected versions
  • < 0.149.7
  • < 224.0.0.251

Official advisory · high-confidence parse· fetched 12 days ago·verify at source

Fixed versions
  • 0.149.7

Official advisory · high-confidence parse· fetched 12 days ago·verify at source

Mitigation checklist

Recommended fix / mitigation
  • Upgrade to zeroconf 0.149.7 or later once packaged in the affected Red Hat product. Where upgrading isn't immediately possible, restricting the affected host's exposure to the local network segment (network segmentation or firewalling multicast DNS traffic on UDP/5353) reduces the practical attack surface, since exploitation requires local-link access.

Official advisory · high-confidence parse· fetched 12 days ago·verify at source

Discussion(0)

No comments yet. Share field notes, upgrade gotchas, or questions — verify against the vendor advisory before acting on community advice.

Sign in to join the discussion.