CVE-2026-33064

free5GC UDM DataChangeNotification Procedure Panic Due to Nil Pointer Dereference

HIGH
7.5
CVSS Score
Published: March 20, 2026 at 08:00 AM UTC
Updated: June 17, 2026 at 10:36 AM UTC
2 products affected across 1 vendorUdmFREE5GC

Using free5gc by free5gc?

Get instant alerts when new vulnerabilities affect free5gc - before attackers find them.

Real-time alertsTrack your software stackFree plan available
Severity
HIGH7.5
Exploit prediction
EPSS 0.5%
SSVC
PoC

Description

Free5GC is an open-source Linux Foundation project for 5th generation (5G) mobile core networks. Versions prior to 1.4.2 are vulnerable to procedure panic caused by Nil Pointer Dereference in the /sdm-subscriptions endpoint. A remote attacker can cause the UDM service to panic and crash by sending a crafted POST request to the /sdm-subscriptions endpoint with a malformed URL path containing path traversal sequences (../) and a large JSON payload. The DataChangeNotificationProcedure function in notifier.go attempts to access a nil pointer without proper validation, causing a complete service crash with "runtime error: invalid memory address or nil pointer dereference". Exploitation would result in UDM functionality disruption until recovery by restart. This issue has been fixed in version 1.4.2.

Affected

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

v < 1.4.2
v < 1.4.2
Affected range stops below 1.4.2, so it looks safe — our inference, not a vendor statement

References (4)

x_refsource_CONFIRMPatchVendor Advisory
Source: cverecord
https://github.com/free5gc/free5gc/security/advisories/GHSA-7g27-v5wj-jr75
x_refsource_MISCExploitIssue TrackingPatchVendor Advisory
Source: cverecord
https://github.com/free5gc/free5gc/issues/781
x_refsource_MISCIssue TrackingPatch
Source: cverecord
https://github.com/free5gc/udm/pull/78

SSVC — Action Prioritization

SSVCPoCAutomatablePartial 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
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusANALYZED
CWE
CWE-478CWE-476

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