{"cve":"CVE-2026-40249","nvd":{"published":"2026-04-16T22:16:38.793","modified":"2026-06-17T10:44:54.463","status":"Analyzed","description":"free5GC is an open-source implementation of the 5G core network. In versions 4.2.1 and below of the UDR service, the PUT handler for updating Policy Data notification subscriptions at /nudr-dr/v2/policy-data/subs-to-notify/{subsId} does not return after request body retrieval or deserialization errors. Although HTTP 500 or 400 error responses are sent, execution continues and the processor is invoked with a potentially uninitialized or partially initialized PolicyDataSubscription object. This fail-open behavior may allow unintended modification of existing Policy Data notification subscriptions with invalid or empty input, depending on downstream processor and storage behavior. A patched version was not available at the time of publication.","cvss_v4":{"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N","score":6.9},"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","score":5.3},"cwes":["CWE-636","CWE-754"],"references":["https://github.com/free5gc/free5gc/security/advisories/GHSA-gx38-8h33-pmxr"],"products":["free5gc:free5gc"],"source":"nvd","synced_at":"2026-10-19T22:30:49.762551342+00:00"},"epss":{"cve":"CVE-2026-40249","score":0.00321,"percentile":0.25141,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-gx38-8h33-pmxr","url":"https://osv.dev/vulnerability/GHSA-gx38-8h33-pmxr","summary":"free5gc UDR fail-open request handling in PolicyDataSubsToNotifySubsIdPut may allow unintended subscription updates after input errors","modified":"2026-06-25T23:11:36.332076796Z","packages":[{"ecosystem":"Go","name":"github.com/free5gc/udr","purl":"pkg:golang/github.com/free5gc/udr","ranges":["<=1.4.2"],"fixed":[]}]},{"id":"GO-2026-5407","url":"https://osv.dev/vulnerability/GO-2026-5407","summary":"free5gc UDR fail-open request handling in PolicyDataSubsToNotifySubsIdPut may allow unintended subscription updates after input errors in github.com/free5gc/udr","modified":"2026-06-25T23:00:16.072699662Z","packages":[{"ecosystem":"Go","name":"github.com/free5gc/udr","purl":"pkg:golang/github.com/free5gc/udr","ranges":["all versions"],"fixed":[]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}