CVE-2026-40343 json
free5GC UDR: Fail-open handling in PolicyDataSubsToNotifyPost allows unintended subscription creation
published 2026-04-21 6 mo ago modified 2026-10-26 13 d ago also GHSA-jwch-w7wh-gqjm , GO-2026-5482 , EUVD-2026-24555
- cvss
- 5.8
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 8.6%
- EPSS 8.6% chance of exploitation in 30 days, percentile 95%
- public exploits
- 0
- none known
Summary
free5GC UDR is the user data repository (UDR) for free5GC, an an open-source project for 5th generation (5G) mobile core networks. In versions up to and including 1.4.2, a fail-open request handling flaw in the UDR service causes the `/nudr-dr/v2/policy-data/subs-to-notify` POST handler to continue processing requests even after request body retrieval or deserialization errors. This may allow unintended creation of Policy Data notification subscriptions with invalid, empty, or partially processed input, depending on downstream processor behavior. As of time of publication, a patched version is not available.
Patch / fix
- govulncheck-vulndb openSUSE Leap 16.0 0.0.20260723T184607-160000.1.1
opensuse advisories openSUSE-SU-2026:21483-1
CISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 6 mo ago
Exploit prediction
8.63% chance of exploitation in the next 30 days, higher than 95% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 6.9 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N |
| CNA | 4.0 | 6.9 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
| NVD | 3.1 | 5.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N |
| GitHub | 3.1 | 5.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| go | github.com/free5gc/udr | <=1.4.2 all versions |
no fix listed |
Affected products
- free5gc udr
Classification
- Weakness
-
- CWE-754 Improper Check for Unusual or Exceptional Conditions
References
-
github.com
/free5gc/free5gc/security/advisories/GHSA-jwch-w7wh-gqjm
web, mitigation, patch, vendor-advisory, advisory
-
nvd.nist.gov
/vuln/detail/CVE-2026-40343
advisory
-
github.com
/free5gc/free5gc
package
Sources
- CVE List CVE-2026-40343
- GitHub Advisory GHSA-jwch-w7wh-gqjm
- NVD CVE-2026-40343
- OSV GO-2026-5482
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.