Cyber Posture

CVE-2026-1682

MediumPublic PoC

Published: 30 January 2026

Published
30 January 2026
Modified
23 February 2026
KEV Added
Patch
CVSS Score 5.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
EPSS Score 0.0004 12.8th percentile
Risk Priority 11 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2026-1682 is a medium-severity Improper Resource Shutdown or Release (CWE-404) vulnerability in Free5Gc Free5Gc. Its CVSS base score is 5.3 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 12.8th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

Threat & Defense at a Glance

What attackers do: exploitation maps to Exploit Public-Facing Application (T1190) and 1 other technique.
Threat & Defense Details

Likely Mitigating ControlsAI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-404

Contingency plan updates incorporate proper resource shutdown and release steps, preventing attackers from leveraging incomplete cleanup during recovery scenarios.

addresses: CWE-404

Mandates explicit shutdown of the network connection at session conclusion, directly addressing improper resource release.

addresses: CWE-404

Requires proper shutdown/release procedures that include overwriting or isolating data to block unintended transfer via reused system objects.

addresses: CWE-404

Procedures can mandate orderly shutdown or release of resources when failures occur, preventing improper resource handling after a fault.

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
T1499.004 Application or System Exploitation Impact
Adversaries may exploit software vulnerabilities that can cause an application or system to crash and deny availability to users.
Why these techniques?

Null dereference in network-exposed PFCP handler enables remote unauthenticated exploitation of public-facing app (T1190) resulting in application DoS via crafted requests (T1499.004).

Confidence: HIGH · MITRE ATT&CK Enterprise v18.1

NVD Description

A flaw has been found in Free5GC SMF up to 4.1.0. Affected is the function HandlePfcpAssociationReleaseRequest of the file internal/pfcp/handler/handler.go of the component PFCP UDP Endpoint. Executing a manipulation can lead to null pointer dereference. The attack may be launched…

more

remotely. The exploit has been published and may be used. A patch should be applied to remediate this issue.

Deeper analysisAI

CVE-2026-1682 is a null pointer dereference vulnerability (CWE-404, CWE-476) in the Free5GC SMF (Session Management Function) up to version 4.1.0. The flaw affects the HandlePfcpAssociationReleaseRequest function within the PFCP UDP Endpoint component, specifically in the file internal/pfcp/handler/handler.go. It has a CVSS v3.1 base score of 5.3 (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L), indicating medium severity with low availability impact but no confidentiality or integrity effects.

The vulnerability can be exploited remotely by unauthenticated attackers over the network with low complexity and no user interaction required. Successful exploitation triggers a null pointer dereference, potentially causing a denial-of-service condition through application crashes or instability in the PFCP UDP Endpoint handling.

GitHub advisories in free5gc/free5gc issue #794 and related comments detail the issue, with a patch available in free5gc/smf pull request #188. Security practitioners should apply this patch to remediate the vulnerability.

An exploit for this issue has been publicly disclosed, increasing the risk of targeted attacks against exposed Free5GC SMF deployments.

Details

CWE(s)

Affected Products

free5gc
free5gc
≤ 4.1.0

CVEs Like This One

CVE-2026-1975Same product: Free5Gc Free5Gc
CVE-2026-1974Same product: Free5Gc Free5Gc
CVE-2026-1973Same product: Free5Gc Free5Gc
CVE-2026-1976Same product: Free5Gc Free5Gc
CVE-2026-33063Same product: Free5Gc Free5Gc
CVE-2026-1683Same product: Free5Gc Free5Gc
CVE-2026-2525Same product: Free5Gc Free5Gc
CVE-2026-1684Same product: Free5Gc Free5Gc
CVE-2026-33062Same product: Free5Gc Free5Gc
CVE-2025-70122Same product: Free5Gc Free5Gc

References