CVE Explorer
CVE-2026-50252
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 randomizat
Known exploited
Not asserted
Disputed
No
Stale source
No
Conflicts
0
Affected products and versions
1 source assertion{"defaultStatus":"unaffected","product":"Unbound","vendor":"NLnet Labs","versions":[{"lessThan":"1.25.2","status":"affected","version":"1.4.22","versionType":"semver"}]}
- cve_program_cvelist_v5affectedurn:baitaphish:normalized-source-record:v2:bae869cf7e634e3fc253f1a25691f0cde49f38c63986a579019d5c11bc3ccabe · sha256:e15d29d2904a65c1… · /containers/cna/affected/0
Provider-owned CVSS observations
1 source assertion{"metric":{"baseScore":5.7,"baseSeverity":"MEDIUM","vectorString":"CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:H/SA:H/E:P/U:Amber","version":"4.0"},"metric_type":"cvssV4_0"}
- cve_program_cvelist_v5cvssurn:baitaphish:normalized-source-record:v2:bae869cf7e634e3fc253f1a25691f0cde49f38c63986a579019d5c11bc3ccabe · sha256:e15d29d2904a65c1… · /containers/cna/metrics/0/cvssV4_0
CWE assertions
1 source assertion{"cweId":"CWE-349","description":"CWE-349: Acceptance of Extraneous Untrusted Data With Trusted Data","lang":"en","type":"CWE"}
- cve_program_cvelist_v5cweurn:baitaphish:normalized-source-record:v2:bae869cf7e634e3fc253f1a25691f0cde49f38c63986a579019d5c11bc3ccabe · sha256:e15d29d2904a65c1… · /containers/cna/problemTypes/0/descriptions/0
Source references
1 source assertion{"tags":["vendor-advisory"],"url":"https://www.nlnetlabs.nl/downloads/unbound/CVE-2026-50252.txt"}
- cve_program_cvelist_v5referenceurn:baitaphish:normalized-source-record:v2:bae869cf7e634e3fc253f1a25691f0cde49f38c63986a579019d5c11bc3ccabe · sha256:e15d29d2904a65c1… · /containers/cna/references/0
Attribution and limitations
- CVE Program CVEList V5: Reproduce the MITRE copyright designation and CVE license in copies. Source →
Provider severity values are preserved separately. Baitaphish does not convert them into a risk rating, infer affected products, or treat EPSS as observed exploitation.