CVE-2026-40343

free5GC UDR: Fail-open handling in PolicyDataSubsToNotifyPost allows unintended subscription creation

MEDIUM
5.8
CVSS Score
Published: April 21, 2026 at 11:47 PM UTC
Updated: June 17, 2026 at 10:45 AM UTC
2 products affected across 1 vendorFREE5GCUDR

Using udr by free5gc?

Get instant alerts when new vulnerabilities affect udr - before attackers find them.

Real-time alertsTrack your software stackFree plan available
Severity
MEDIUM5.8
Exploit prediction
EPSS 9%
SSVC
No known exploit

Description

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v ≤ 4.2.1
v ≤ 1.4.2<= 1.4.2

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (1)

x_refsource_CONFIRMMitigationPatchVendor Advisory
Source: cverecord
https://github.com/free5gc/free5gc/security/advisories/GHSA-jwch-w7wh-gqjm

SSVC — Action Prioritization

SSVCNo known exploitAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
CHANGED
Confidentiality
NONE
Integrity
LOW
Availability
NONE
Vector?

Quick Info

StatusANALYZED
CWE
CWE-754

Get alerted

Stop reading CVE feeds looking for your own stack

Track the products you run and VulnTracker tells you when a new CVE affects them — with what is known about fixing it, and nothing about the rest.

Free plan, no card