4.3
MEDIUM CVSS 3.1
CVE-2026-7781
Open5GS amf-3gpp-access Endpoint nudm-handler.c udm_nudm_uecm_handle_amf_registration_update denial of service
Description

A security vulnerability has been detected in Open5GS up to 2.7.7. Affected by this issue is the function udm_nudm_uecm_handle_amf_registration_update of the file /src/udm/nudm-handler.c of the component amf-3gpp-access Endpoint. The manipulation leads to denial of service. The attack is possible to be carried out remotely. The exploit has been disclosed publicly and may be used. The project was informed of the problem early through an issue report but has not responded yet.

INFO

Published Date :

May 4, 2026, 11:16 p.m.

Last Modified :

May 4, 2026, 11:16 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-7781 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 2.0 MEDIUM [email protected]
CVSS 3.1 MEDIUM [email protected]
CVSS 4.0 LOW [email protected]
Solution
Update Open5GS to a version that addresses the denial of service vulnerability.
  • Update Open5GS to version 2.7.8 or later.
  • Apply any available security patches for Open5GS.
  • Monitor for further project responses or advisories.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-7781.

URL Resource
https://github.com/open5gs/open5gs/
https://github.com/open5gs/open5gs/issues/4420
https://vuldb.com/submit/806251
https://vuldb.com/vuln/360978
https://vuldb.com/vuln/360978/cti
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-7781 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-7781 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-7781 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-7781 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    May. 04, 2026

    Action Type Old Value New Value
    Added Description A security vulnerability has been detected in Open5GS up to 2.7.7. Affected by this issue is the function udm_nudm_uecm_handle_amf_registration_update of the file /src/udm/nudm-handler.c of the component amf-3gpp-access Endpoint. The manipulation leads to denial of service. The attack is possible to be carried out remotely. The exploit has been disclosed publicly and may be used. The project was informed of the problem early through an issue report but has not responded yet.
    Added CVSS V4.0 AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P/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
    Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
    Added CVSS V2 (AV:N/AC:L/Au:S/C:N/I:N/A:P)
    Added CWE CWE-404
    Added Reference https://github.com/open5gs/open5gs/
    Added Reference https://github.com/open5gs/open5gs/issues/4420
    Added Reference https://vuldb.com/submit/806251
    Added Reference https://vuldb.com/vuln/360978
    Added Reference https://vuldb.com/vuln/360978/cti
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.