CVE-2026-44328

HIGH EPSS 24.1%
Published May 27, 20261mo ago · Modified Jun 17, 20262w ago
8.2 CVSS 3.1
High
Find Similar
Published May 27, 2026 1mo ago
Last Modified Jun 17, 2026 2w ago

Description

free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's SMF mounts the UPI management route group without inbound OAuth2 middleware. On top of that, the DELETE /upi/v1/upNodesLinks/{upNodeRef} handler unconditionally dereferences upNode.UPF after the type-guarded async release, even though AN-typed nodes are constructed without a UPF object. As a result, a single unauthenticated DELETE /upi/v1/upNodesLinks/gNB1 request crashes the handler with a nil-pointer panic AND mutates the in-memory user-plane topology before panicking (the UpNodeDelete(upNodeRef) line runs first). This is an unauthenticated, state-mutating panic-DoS sink that an off-path network attacker can trigger by name against any AN entry. This vulnerability is fixed in 4.2.2.

CVSS Details

Base Score
8.2
Exploitability
3.9
Impact
4.2
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H
Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope Unchanged
Confidentiality None
Integrity Low
Availability High

Threat Intelligence

EPSS Exploit Probability
24.1% percentile
Exploit & Patch Status
Public Exploit Known
Patch Available

Weaknesses 3

CWE-306 Missing Authentication for Critical Function Authentication
CWE-476 NULL Pointer Dereference Memory Safety
CWE-862 Missing Authorization Authorization

Affected Products 1

VendorProductVersionRange
free5gcfree5gc* <4.2.2

References 4

  • github.com https://github.com/free5gc/free5gc/issues/905
    ExploitIssue Tracking
  • github.com https://github.com/free5gc/free5gc/security/advisories/GHSA-p9mg-74mg-cwwr
    ExploitVendor Advisory
  • github.com https://github.com/free5gc/smf/commit/b57bc48081c3d3a2f333d02eb78e4fd31a120deb
    Patch
  • github.com https://github.com/free5gc/smf/pull/199
    Issue TrackingPatch

Remediation

  • github.com https://github.com/free5gc/smf/commit/b57bc48081c3d3a2f333d02eb78e4fd31a120deb
    Patch
  • github.com https://github.com/free5gc/smf/pull/199
    Issue TrackingPatch