CVE-2026-47184 is a medium-severity uncontrolled resource consumption vulnerability in zeroconf (pip), affecting versions < 0.149.7. It is fixed in 0.149.7.
Impact DNSCache.asyncadd inserted every response record into cache, expirations, expireheap, and servicecache with no cap on entry count. The only pre-existing protection was a PTR TTL floor (DNSPTRMINTTL = 1125 s, RFC 6762 §10), which actually prolonged attacker-injected records, and a periodic asyncexpire on CACHECLEANUPINTERVAL = 10 s that could not keep up with a flood. Any unauthenticated host on the local link (UDP/5353, 224.0.0.251 / ff02::fb) can multicast valid mDNS responses with unique names (RFC 6762 §11 allows up to 253 bytes each) and watch them accumulate. On memory-constrained deployments (Home Assistant on Raspberry-Pi-class hardware is the canonical victim) sustained traffic OOM-kills the process; under lighter load, every cache lookup and every periodic expiry pass grows linearly slower, starving asyncio and breaking unrelated zeroconf consumers (discovery, registration, ServiceBrowser callbacks). A second variant, re-multicasting cached records with shifting TTLs, grows expireheap unbounded between cleanup runs without touching cache or totalrecords. Patches Fixed in zeroconf 0.149.6 (PR #1718). Upgrade to >= 0.149.6. Workarounds There is no in-process workaround; upgrading is the fix. Otherwise, restrict mDNS (UDP/5353) to trusted Layer-2 segments via AP client isolation, guest-network separation, or host firewall rules. Resources PR #1718, fix Issue #1715, public tracking issue RFC 6762 §10, RFC 6762 §11, CWE-400
Crafted input forces the application to consume excessive CPU, memory, or other resources, degrading or denying service. Typical impact: denial of service.
CVE-2026-47184 has a CVSS score of 6.5 (Medium). The vector is reachable from an adjacent network, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment.
A fixed version is available (0.149.7). Upgrading removes the vulnerable code path.
pip
zeroconf (< 0.149.7)zeroconf → 0.149.7 (pip)Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
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CVE-2026-47184 is a medium-severity uncontrolled resource consumption vulnerability in zeroconf (pip), affecting versions < 0.149.7. It is fixed in 0.149.7. Crafted input forces the application to consume excessive CPU, memory, or other resources, degrading or denying service.
CVE-2026-47184 has a CVSS score of 6.5 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
zeroconf (pip) versions < 0.149.7 is affected.
Yes. CVE-2026-47184 is fixed in 0.149.7. Upgrade to this version or later.
Whether CVE-2026-47184 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
Upgrade zeroconf to 0.149.7 or later.