In NLnet Labs Unbound 1.4.22 up to and including 1.25.1, UDP source port is randomized and intended to serve as a secret value that increases the…
In NLnet Labs Unbound 1.4.22 up to and including 1.25.1, UDP source port is randomized and intended to serve as a secret value that increases the entropy of DNS transactions. When resolver load balancing policies depend on the source port while their outcome is revealed this secrecy is undermined. The vulnerability arises when the load balancing policy is consistent with respect to the incoming source UDP port and IP address while heavily depending on the incoming source UDP port as a randomization source. When the SO_REUSEPORT configuration option is enabled ('so-reuseport: yes') in Unbound (
Read at NIST National Vulnerability Database (CVE API 2.0)
- Product
- dnsmasq / Unbound / PowerDNS
- EPSS
- 0.002 (p7)
- Exposure class
- Edge / VPN / firewall
Why it ranks 24 (Routine)
- Exposed product class: edge / VPN / firewall
- Covered by 3 independent sources
- Recency: items published within 24 hours gain 15, within 72 hours 6, within 7 days 2.
Links
- NIST National Vulnerability Database (CVE API 2.0) (nvd.nist.gov)
- CVE-2026-50252 on this site · NVD · CVE.org · Vulnpedia
Related coverage
Other items that share a CVE or were clustered with this one.