CVE-2026-4531 json
Free5GC AMF handler.go HandleRegistrationComplete denial of service
published 7mo ago modified 4mo ago also GHSA-xq44-64rg-8g3h , GO-2026-5767 , EUVD-2026-14264
- cvss
- 5.3
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.4%
- EPSS 0.4% chance of exploitation in 30 days, percentile 38%
- public exploits
- 0
- none known
Summary
A weakness has been identified in Free5GC 4.1.0. Affected is the function HandleRegistrationComplete of the file internal/gmm/handler.go of the component AMF. Executing a manipulation can lead to denial of service. The attack may be performed from remote. This patch is called 52e9386401ce56ea773c5aa587d4cdf7d53da799. It is best practice to apply a patch to resolve this issue.
Patch / fix
- go github.com/free5gc/amf 1.4.3-0.20260306074636-52e9386401ce
- govulncheck-vulndb openSUSE Leap 16.0 0.0.20260723T184607-160000.1.1
opensuse advisories openSUSE-SU-2026:21483-1
- github.com/free5gc/amf@52e9386 commit
- github.com/free5gc/amf#198 pull request
Is CVE-2026-4531 in your dependencies? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerCISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 7mo ago
Exploit prediction
0.44% chance of exploitation in the next 30 days, higher than 38% of all scored CVEs (FIRST EPSS, 2026-11-09).
Exploits and checks
- github.com https://github.com/free5gc/free5gc/issues/792 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 6.9 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X |
| CNA | 3.1 | 5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L/E:X/RL:O/RC:C |
| CNA | 3.0 | 5.3 | CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L/E:X/RL:O/RC:C |
| CNA | 2.0 | 5.0 | AV:N/AC:L/Au:N/C:N/I:N/A:P/E:ND/RL:OF/RC:C |
| CNA | 4.0 | 6.9 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
| CNA | 3.1 | 5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L |
| CNA | 2.0 | 5.0 | AV:N/AC:L/Au:N/C:N/I:N/A:P |
| GitHub | 3.1 | 5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| go | github.com/free5gc/amf | <1.4.3-0.20260306074636-52e9386401ce |
1.4.3-0.20260306074636-52e9386401ce |
Affected products
- n/a Free5GC
Classification
- Weakness
-
- CWE-404 Improper Resource Shutdown or Release
References
-
github.com
/free5gc/amf/pull/198
issue-tracking, patch, web
-
github.com
/free5gc/amf/commit/52e9386401ce56ea773c5aa587d4cdf7d53da799
patch, web
-
github.com
/free5gc/free5gc/issues/792
issue-tracking, exploit, web
-
vuldb.com
/?id.352319
vdb-entry, technical-description, web
-
vuldb.com
/?ctiid.352319
signature, permissions-required, web
-
vuldb.com
/?submit.774073
third-party-advisory, web
-
github.com
/free5gc/free5gc/
product
-
nvd.nist.gov
/vuln/detail/CVE-2026-4531
advisory
-
github.com
/free5gc/amf
package
-
github.com
/advisories/GHSA-xq44-64rg-8g3h
advisory
Sources
- CVE List CVE-2026-4531
- GitHub Advisory GHSA-xq44-64rg-8g3h
- NVD CVE-2026-4531
- OSV GO-2026-5767
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.