Vulnerability in Open5gs

CVE-2026-4240

A vulnerability was determined in Open5GS up to 2.7.6. The affected element is the function smf_gx_cca_cb/smf_gy_cca_cb/smf_s6b_aaa_cb/smf_s6b_sta_cb of the component CCA Handler. This manipulation causes denial of service. The attack can be initiated remotely. The exploit has been publicly disclosed and may be utilized. Upgrading to version 2.7.7 is sufficient to fix this issue. Patch name: 80eb484a6ab32968e755e628b70d1a9c64f012ec. Upgrading the affected component is recommended.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L.

EPSS exploit prediction

EPSS: 0.009 (57.7th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 58th percentile — 57.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-4240: held from 0.005 to 0.009.

EPSS over last 30 days · oldest: 0.005 · newest: 0.009 · change: +0.004

Affected products

  • Open5gs
  • Open5gs — versions 2.7.0, 2.7.1, 2.7.2

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-4240?
CVE-2026-4240 is a medium-severity vulnerability in Open5gs, classified under Improper Resource Shutdown or Release. CVSS score: 5.3/10. Published 2026-03-16.
How severe is CVE-2026-4240?
Medium severity. CVSS v3 base score is 5.3 out of 10.