Quick answers
- Is CVE-2026-30057 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-30057 being exploited in the wild.
- How severe is CVE-2026-30057?
- High severity, with a CVSS score of 7.5, published 27 August 2026.
- Which products and versions are affected?
- free5GC v4.1.0.
- Is there a fix for CVE-2026-30057?
- No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
- How is CVE-2026-30057 attacked?
- It is attacked over the network, in a hosted service.
- Am I affected by CVE-2026-30057?
- Check whether you run free5GC 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 an unhandled panic in the CreateUEContext handler (HTTPCreateUEContext in api_communication.go) when processing requests with Content-Type: multipart/related. The root cause is improper deserialization in the openapi.MultipartDeserialize function, which attempts an illegal reflection operation (FieldByName on a slice type) when parsing the multipart payload. This causes an unrecoverable panic that crashes the AMF process. The attack requires no authentication and is network-reachable at the SBI endpoint, allowing any attacker with network access to the AMF to trigger a denial of service. A patch addressing the improper deserialization logic is needed to either correctly handle multipart/related content or reject it gracefully.
Affected products
- free5gc free5gc v4.1.0
Timeline
- 2026-01-01: disclosed: Issue reported on GitHub #755
- 2026-08-27: advisory: CVE-2026-30057 published