DNS resolver cache poisoning could disrupt core infrastructure and affect many organizations; widely impactful.
CVE-2025-59023
DNS recursor cache poisoning via crafted delegations or IP fragments
Is CVE-2025-59023 being exploited?
Not confirmed. CVE-2025-59023 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.28% probability of exploitation in the next 30 days.
How severe is CVE-2025-59023?
CVE-2025-59023 is rated High with a CVSS score of 8.2. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2025-59023?
Yes. A fix has been recorded for CVE-2025-59023. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2025-59023 affect?
CVE-2025-59023 affects DNS resolvers, Caching DNS servers, Recursor implementations. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2025-59023?
Patch when released; monitor DNS traffic and cache activity.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Remote cache poisoning of DNS recursor enables redirection to attacker-controlled hosts.
Patch when possible
- affected>= 5.3.0 and < 5.3.1
- affected>= 5.2.0 and < 5.2.6
- affected>= 5.1.0 and < 5.1.8
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.