CVE-2026-40245: Free5GC is an open-source Linux Foundation project for 5th generation (5G) mobile core networks

Q: How do I fix CVE-2026-40245?

free5gc: upgrade to newer than 4.2.1. Exact commands for each OS are on this page.

Q: Is CVE-2026-40245 being exploited?

CVE-2026-40245 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

Q: What does CVE-2026-40245 affect?

CVE-2026-40245 affects free5gc. Severity is high (CVSS 7.5). Free5GC is an open-source Linux Foundation project for 5th generation (5G) mobile core networks. Versions 4.2.1 and below contain an information disclosure vulnerability in the UDR (Unified Data Repository) service. The handler for GET /nud

Q: How urgent is CVE-2026-40245?

Priority 52/100. High severity; Public exploit reference; Remotely exploitable, no login, no user action; On your watchlist

This week

HIGH 7.5REMOTEWATCHLISTUPGRADE

CVE-2026-40245 is a high-severity flaw (CVSS 7.5) affecting free5gc. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

Free5GC is an open-source Linux Foundation project for 5th generation (5G) mobile core networks. Versions 4.2.1 and below contain an information disclosure vulnerability in the UDR (Unified Data Repository) service. The handler for GET /nudr-dr/v2/application-data/influenceData/subs-to-notify sends an HTTP 400 error response when required query parameters are missing but does not return afterward. Execution continues into the processor function,

Why this priority

High severity
Public exploit reference
Remotely exploitable, no login, no user action
On your watchlist

A fixed release or distro patch exists.

Risk facts

CVSS score	7.5 (High)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	0.5% (top 57%)
CISA exploited list	No
Weakness	CWE-200, CWE-202, CWE-209
Published	2026-04-16
Last modified	2026-06-17

Publisher (CNA): GitHub, Inc. · Vendor: free5gc

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2026-04-16 00:16 UTCPublished CVE record published
2026-06-17 10:44 UTCUpdated Record last modified

free5gc free5gc UPGRADE

Affected: <= 4.2.1

Fixed in: newer than 4.2.1

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy free5gc || rpm -q free5gc || free5gc --version

2. UPGRADE to newer than 4.2.1 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade free5gc

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade free5gc

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2026-40245?

free5gc: upgrade to newer than 4.2.1. Exact commands for each OS are on this page.

Is CVE-2026-40245 being exploited?

CVE-2026-40245 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2026-40245 affect?

CVE-2026-40245 affects free5gc. Severity is high (CVSS 7.5). Free5GC is an open-source Linux Foundation project for 5th generation (5G) mobile core networks. Versions 4.2.1 and below contain an information disclosure vulnerability in the UDR (Unified Data Repository) service. The handler for GET /nud

How urgent is CVE-2026-40245?

Priority 52/100. High severity; Public exploit reference; Remotely exploitable, no login, no user action; On your watchlist

Related CVEs

CVE-2026-40343 MEDIUM 5.8 UPGRADE UPGRADE free5GC UDR is the user data repository (UDR) for free5GC, an an open-source project for 5th generation (5G) m
CVE-2026-41135 HIGH 7.5 UPGRADE UPGRADE free5GC UDR is the Policy Control Function (PCF) for free5GC, an an open-source project for 5th generation (5G
CVE-2026-41136 MEDIUM 5.3 UPGRADE UPGRADE free5GC AMF provides Access & Mobility Management Function (AMF) for free5GC, an an open-source project for 5t
CVE-2026-44329 CRITICAL 10.0 UPGRADE free5GC is an open-source implementation of the 5G core network
CVE-2026-44327 CRITICAL 10.0 UPGRADE free5GC is an open-source implementation of the 5G core network

References

← Back to latest CVEs