CVE-2025-15539 Open5GS sgwc s11-handler.c sgwc_s11_handle_downlink_data_notification_ack denial of service
Remote attackers can cause a denial of service in Open5GS by exploiting a flaw in the SGWC S11 handler, requiring a patch for mitigation.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2025-15539?
CVE-2025-15539 is a medium-severity denial of service vulnerability in Open5gs Open5gs, published on 18 Jan 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
A vulnerability was determined in Open5GS up to 2.7.6. Impacted is the function sgwc_s11_handle_downlink_data_notification_ack of the file src/sgwc/s11-handler.c of the component sgwc. This manipulation causes denial of service. The attack can be initiated remotely. The exploit has been publicly disclosed and may be utilized. Patch name: b4707272c1caf6a7d4dca905694ea55557a0545f. To fix this issue, it is recommended to deploy a patch. The issue report is flagged as already-fixed.
Weakness: CWE-404
Which versions are affected by CVE-2025-15539?
It affects 1 product.
Products include Open5gs Open5gs.
How do I fix CVE-2025-15539?
No fix has been published for CVE-2025-15539 yet. Limit exposure of the affected software until one is available.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2025-15539 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-15539 exists.
Other vulnerabilities in Open5gs Open5gs
Sources
Also known as GHSA-9g9c-c6jm-98g4.