CyberSecBulletin
CVE-2025-8804NVD status: Modified

Open5GS: Reachable Assertion

Published Updated By the CyberSecBulletin desk

CVE-2025-8804 is a high-severity reachable assertion vulnerability in Open5GS, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected Open5GS versions: 2.7.0; 2.7.1; 2.7.2, and others listed below. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.94% chance of exploitation within 30 days, higher than 61% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Check which version of Open5GS you run against the affected versions below, and install the vendor's latest release.
  2. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
Open5GSOpen5GS2.7.0; 2.7.1; 2.7.2; 2.7.3; 2.7.4; 2.7.5Not stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
NoneNo data is disclosed.
Integrity
NoneNothing can be modified.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 4.05.5MediumCNA (vuldb.com)
CVSS 3.15.3MediumCNA (vuldb.com)
CVSS 3.17.5HighNVD
CVSS 2.05.0MediumCNA (vuldb.com)

Official description

A vulnerability was found in Open5GS up to 2.7.5. Affected by this vulnerability is the function ngap_build_downlink_nas_transport of the component AMF. The manipulation leads to reachable assertion. The attack can be launched remotely. The exploit has been disclosed to the public and may be used. Upgrading to version 2.7.6 is able to address this issue. The identifier of the patch is bca0a7b6e01d254f4223b83831162566d4626428. It is recommended to upgrade the affected component.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Reachable Assertion

The product contains an assert() or similar statement that can be triggered by an attacker, which leads to an application exit or other behavior that is more severe than necessary.

How developers prevent this class of flaw

  • If the assertion statement is required (e.g., for security or reliability), change the invoking code to avoid the conditions that trigger the assertion.
  • Consider changing the assertion to some other less fatal error. This might not be easy to implement, since other code may be needed to handle the error.
  • Make sensitive open/close operations non-reachable from directly user-controlled data (e.g. open/close resources)

More Reachable Assertion vulnerabilities (CWE-617)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: poc, automatable: yes, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Third-party and government advisories

Technical write-ups (may include proof of concept)

Other vulnerabilities in Open5GS

All Open5GS vulnerabilities

Recent Reachable Assertion vulnerabilities

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