# CVE-2026-82588: Open5GS null pointer dereference in AMF Transfer Endpoint

Source: https://junglewise.ai/threats/cve-2026-82588-open5gs-null-pointer-dereference-in-amf-transfer-endpoint  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-08-30. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2026-82588 · Severity: medium · CVSS 4.3 · Published 2026-08-30

Open5GS is an open-source implementation of a 5G core network (the backbone infrastructure connecting cellular networks). A null pointer dereference vulnerability in the Access and Mobility Management Function (AMF) Transfer Endpoint could allow remote attackers to crash the service, disrupting mobile network connectivity and potentially affecting millions of subscribers depending on deployment scale.

Technologies: [Open5GS](https://junglewise.ai/threats/technologies/open5gs). Vendors: [Open5GS](https://junglewise.ai/threats/vendors/open5gs).

## Quick answers

**Is CVE-2026-82588 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-82588 being exploited in the wild.

**How severe is CVE-2026-82588?** Medium severity, with a CVSS score of 4.3, published 30 August 2026.

**Which products and versions are affected?** Open5GS up to 2.7.7.

**Is there a fix for CVE-2026-82588?** A patch was published on 2026-05-14: Patch committed as abf8a83; fix included in version 2.8.0 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-82588 attacked?** It is attacked over the network, in a hosted service.

**Am I affected by CVE-2026-82588?** Check whether you run Open5GS at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

The vulnerability is a null pointer dereference in the file src/amf/namf-handler.c within the Transfer Endpoint component of Open5GS. The root cause involves improper handling of unknown NGAP IE types in the amf_namf_comm_handle_n1_n2_message_transfer function, which previously called ogs_assert_if_reached() in the default case, causing an immediate crash. The attack is network-reachable and does not require authentication. An attacker can send crafted N1/N2 message transfers to trigger the null pointer dereference, resulting in denial of service (process crash). The vulnerability affects Open5GS up to version 2.7.7; version 2.8.0 and later address this issue via patch abf8a83, which replaces the assertion with proper error handling.

## Affected products

- Open5GS Open5GS up to 2.7.7

## Timeline

- 2026-08-30: disclosed
- 2026-05-14: patched: Patch committed as abf8a83; fix included in version 2.8.0

## References

- [https://github.com/open5gs/open5gs/](https://github.com/open5gs/open5gs/)
- [https://github.com/open5gs/open5gs/commit/abf8a836564b966b5141110fc25ed413c4f17522](https://github.com/open5gs/open5gs/commit/abf8a836564b966b5141110fc25ed413c4f17522)

## Related threats

- [Open5GS HTTP/2 SBI server memory exhaustion](https://junglewise.ai/threats/cve-2026-106806-a-memory-exhaustion-issue-exists-in-open5gs-v2-8-0-in-the-http-2)
- [open5GS PFCP transaction handling denial of service](https://junglewise.ai/threats/cve-2026-106807-a-denial-of-service-vulnerability-exists-in-open5gs-v2-8-0-in)
- [Open5GS heap out-of-bounds write in multipart parsing](https://junglewise.ai/threats/cve-2026-116543-open5gs-1-3-0-through-2-8-0-contains-a-heap-out-of-bounds-write)
- [Open5GS assertion failure in SGSN context request handling](https://junglewise.ai/threats/cve-2026-108105-open5gs-through-2-8-0-contains-a-reachable-assertion)
- [Open5GS heap out-of-bounds read in PFCP parsing](https://junglewise.ai/threats/cve-2026-108103-open5gs-through-2-8-0-contains-a-heap-out-of-bounds-read)