free5GC hasProtocol Compliance Violation in UPF Leading to SMF Service Disruption
Published Feb 23, 2026
2.7
LOWCVSS 4.0
EPSS 0.37%
Description
free5GC is an open-source project for 5th generation (5G) mobile core networks. free5GC go-upf versions up to and including 1.2.6, corresponding to free5gc smf up to and including 1.4.0, have an Improper Input Validation and Protocol Compliance vulnerability leading to Denial of Service. Remote attackers can disrupt core network functionality by sending a malformed PFCP Association Setup Request. The UPF incorrectly accepts it, entering an inconsistent state that causes subsequent legitimate requests to trigger SMF reconnection loops and service degradation. All deployments of free5GC using the UPF and SMF components may be affected. As of time of publication, a fix is in development but not yet available. No direct workaround is available at the application level. Applying the official patch, once released, is recommended.
Affected products
-
- Version <= 1.2.6StatusaffectedConstraints-
- Version
-
- Version <= 1.4.0StatusaffectedConstraints-
- Version
No data.
No Red Hat product state for this CVE.
No package ranges for this CVE.
Remediation
No remediation recorded yet.
Metrics
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U
1 other source (NVD) ▾
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U/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
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
No CVSS v3.0 score for this CVE.
No CVSS v2.0 score for this CVE.
This CVE is not in the KEV list.
CISA SSVC (Vulnrichment)
Stakeholder-Specific Vulnerability Categorization from CISA ADP.
Exploitation
NoneAutomatable
YesTechnical Impact
PartialDecision
n/aAssessed Feb 25, 2026 · SSVC 2.0.3
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 2, 2026.
Score over time
Feb–Oct 2026- EPSS v4
- EPSS v5
Percentile over time
- EPSS v4
- EPSS v5
Table of values (3 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 2, 2026 | 0.37% (0.00369) | 28.43th | v5 (v2026.06.15) |
| Jun 15, 2026 | 0.36% (0.00355) | 27.17th | v5 (v2026.06.15) |
| Feb 24, 2026 | 0.20% (0.00196) | 41.49th | v4 (v2025.03.14) |
References (2)
- https://github.com/free5gc/free5gc/issues/745 x_refsource_MISCExploitIssue TrackingVendor Advisory
- https://github.com/free5gc/free5gc/security/advisories/GHSA-8m42-qw58-8362 x_refsource_CONFIRMVendor Advisory
| Link | Providers | Tags |
|---|---|---|
| https://github.com/free5gc/free5gc/issues/745 | x_refsource_MISCExploitIssue TrackingVendor Advisory | |
| https://github.com/free5gc/free5gc/security/advisories/GHSA-8m42-qw58-8362 | x_refsource_CONFIRMVendor Advisory |
Change history (0)
No recorded changes yet.