CVE-2022-43677 — In free5GC 3

In free5GC 3.2.1, a malformed NGAP message can crash the AMF and NGAP decoders via an index-out-of-range panic in aper.GetBitString.

01What is this vulnerability?

In free5GC 3.2.1, a malformed NGAP message can crash the AMF and NGAP decoders via an index-out-of-range panic in aper.GetBitString.

02Affected products

Vendor	Product	Versions
n	a / n/a	n/a

03Active exploitation status

Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.

04Recommended remediation

• Patch to a fixed version listed in the vendor advisory (see references below).
• Mitigate with WAF rules, network egress filters, or feature flags where the patch is not yet available.
• Hunt historical logs for exploitation indicators — see Detection signatures below.

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Ask SARA in chat to draft a starting detection for this CVE in your stack of choice.

07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

• Published: 2022-10-24T00:00:00.000Z
• Last modified: 2024-08-03T13:40:05.778Z

09References

• github.com — https://github.com/free5gc/free5gc/issues/402
• www.trendmicro.com — https://www.trendmicro.com/en_us/research/23/j/asn1-vulnerabilities-in-5g-cores.…