CVE-2026-91855
Open5GS PFCP Message handler.c denial of service
Description
A security flaw has been discovered in Open5GS up to 2.7.7. Affected by this vulnerability is an unknown functionality of the file lib/pfcp/handler.c of the component PFCP Message Handler. Performing a manipulation results in denial of service. Remote exploitation of the attack is possible. The exploit has been released to the public and may be used for attacks. The patch is named 028e1dbb5e3271035ccee906ef417a97fc523f71. Applying a patch is the recommended action to fix this issue. CVE-2025-29339 describes a different assertion failure vulnerability in Open5GS UPF.
INFO
Published Date :
Sept. 15, 2026, 5:17 p.m.
Last Modified :
Sept. 16, 2026, 1:42 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 2.0 | MEDIUM | [email protected] | ||||
| CVSS 3.1 | MEDIUM | [email protected] | ||||
| CVSS 4.0 | MEDIUM | [email protected] |
Solution
- Apply the patch 028e1dbb5e3271035ccee906ef417a97fc523f71.
- Update Open5GS to a version with the fix.
- Restart the PFCP Message Handler service.
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-2026-91855.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-91855 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-2026-91855
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-2026-91855 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-91855 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.
-
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Sep. 15, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-91855', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'poc'}, {'automatable': 'yes'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-09-15T17:44:31.315009Z'} -
New CVE Received by [email protected]
Sep. 15, 2026
Action Type Old Value New Value Added Description A security flaw has been discovered in Open5GS up to 2.7.7. Affected by this vulnerability is an unknown functionality of the file lib/pfcp/handler.c of the component PFCP Message Handler. Performing a manipulation results in denial of service. Remote exploitation of the attack is possible. The exploit has been released to the public and may be used for attacks. The patch is named 028e1dbb5e3271035ccee906ef417a97fc523f71. Applying a patch is the recommended action to fix this issue. CVE-2025-29339 describes a different assertion failure vulnerability in Open5GS UPF. Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/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:N/UI:N/S:U/C:N/I:N/A:L Added CVSS V2 (AV:N/AC:L/Au:N/C:N/I:N/A:P) Added CWE CWE-404 Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/91xxx/CVE-2026-91855.json">CVE-2026-91855</a> Added Reference https://github.com/open5gs/open5gs/ Added Reference https://github.com/open5gs/open5gs/commit/028e1dbb5e3271035ccee906ef417a97fc523f71 Added Reference https://github.com/open5gs/open5gs/issues/4699 Added Reference https://vuldb.com/cve/CVE-2026-91855 Added Reference https://vuldb.com/submit/933834 Added Reference https://vuldb.com/vuln/404086 Added Reference https://vuldb.com/vuln/404086/cti