A resource exhaustion issue exists in Free5GC v4.2.3 during PFCP Session Establishment failure handling.
Written by anthropic/claude-haiku-5.5 from the sources below. Verify against them.
- Exploited
- No known exploitation
- Fix
- No fix listed
- Who is exposed
- Not reported
Do first: Workaround: The checked facts contain no workaround. Watch for repeated PFCP session establishment failures on the SMF, since these are the condition that exhausts the UE IP address pool.
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- Published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- A 0-100 score for how much a CVE matters across the industry: exploitation, exposure, how widely the software is used, severity and whether a fix exists.What do these mean? →
- 5/100 · provisional
- How many real-world setups can hit the bug, from the vendor's advisory and CISA data. It does not know your setup.What do these mean? →
- Unclear
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
Free5GC, an open-source 5G core network implementation, is affected, specifically its Session Management Function (SMF) component. Repeated failed PFCP session setups can leave UE IP addresses unreleased, exhausting the address pool and preventing new devices from establishing data sessions, which causes a denial of service.
Read the original description
A resource exhaustion issue exists in Free5GC v4.2.3 during PFCP Session Establishment failure handling. When the SMF does not receive a PFCP Session Establishment Response from the UPF, allocated UE IP address resources are not properly released. Repeated failed session establishment attempts can therefore exhaust the UE IP address pool, preventing new UEs from establishing PDU sessions and resulting in denial of service.
What to do
Workaround: The checked facts contain no workaround. Watch for repeated PFCP session establishment failures on the SMF, since these are the condition that exhausts the UE IP address pool.
Timeline
- CVE published
- Record last updated
- First seen by cve.now
Evidence 3
- Repository
- Repository
- Link
Corrections
None so far.
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Questions about CVE-2026-106805
What does this mean?
When the SMF does not get a PFCP Session Establishment Response from the UPF and then cannot deliver the PDU Session Establishment Reject to the AMF, it fails to release the session context and its UE IP address. Repeated failures use up the UE IP address pool, so new UEs cannot set up PDU sessions.Source: github.com
Am I affected, and how do I check?
The facts name Free5GC v4.2.3 and a setup where PFCP Session Establishment Responses from the UPF are not received and the PDU Session Establishment Reject cannot reach the AMF after a PFCP timeout. To check a deployment, confirm the Free5GC version it runs and whether it is v4.2.3.Source: github.com
What should I do about it?
No fixed version is given in the checked facts, so no upgrade target can be named from them. Check the Free5GC project for a release that fixes this issue.Source: github.com
Is it being exploited?
It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked.Source: cve.now feed data
What if there's no patch?
The checked facts contain no workaround. Watch for repeated PFCP session establishment failures on the SMF, since these are the condition that exhausts the UE IP address pool.Source: github.com