Security readout for executives and security teams
Plain-English summary
CVE-2026-1682 can let a remote unauthenticated attacker crash or disrupt the Free5GC SMF PFCP UDP endpoint by triggering a null pointer error. Business impact is denial of service for affected 5G core lab or production deployments using Free5GC SMF 4.0 or 4.1.0.
Executive priority
Prioritize remediation where Free5GC SMF supports important testing, research, or production 5G core functions. Treat as a service availability risk. Urgency increases if PFCP is reachable outside tightly controlled network segments.
Technical view
The flaw is in Free5GC SMF internal/pfcp/handler/handler.go, function HandlePfcpAssociationReleaseRequest. Manipulated PFCP Association Release Request handling can cause a null pointer dereference. CVSS 4.0 is 6.9: network reachable, low complexity, no privileges, no user interaction, with low availability impact.
Likely exposure
Exposure is limited to environments running Free5GC SMF 4.0 or 4.1.0 with the PFCP UDP endpoint reachable by untrusted or semi-trusted networks. Internet exposure is not stated in the sources; validate network placement and filtering.
Exploitation context
The source bundle states an exploit has been published and may be used. There is no KEV listing and no cited evidence of active exploitation. The likely outcome is service disruption rather than data theft or privilege escalation, based on the provided CVSS impacts.
Researcher notes
Sources identify CWE-476 and CWE-404, a vulnerable handler function, affected Free5GC SMF versions 4.0 and 4.1.0, and a patch-related GitHub pull request. The sources do not provide a named fixed release in the bundle, so verify upstream status before closure.
Mitigation direction
- Identify Free5GC SMF deployments and confirm versions.
- Apply the vendor patch or upgrade per Free5GC guidance.
- Review GitHub PR 188 for remediation status before deployment.
- Restrict PFCP UDP endpoint access to trusted network peers.
- Monitor SMF stability and unexpected PFCP-related crashes.
Validation and detection
- Inventory Free5GC SMF versions across lab and production environments.
- Confirm whether versions 4.0 or 4.1.0 are deployed.
- Check whether the PFCP UDP endpoint is reachable from untrusted networks.
- Review SMF logs for crashes around PFCP association release handling.
- Track the Free5GC issue and pull request for fix confirmation.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-404: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCWE-476: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2026-1682 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Medium
- CVSS
- 6.9 (4.0)
- Known Exploited
- No
- Published
Vector: 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:P
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
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:P——Primary CVE scoreVulnerability scoring details
Base CVSS 4.0 score
6.9MediumVector: 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:P
Source materials
- CVE List V5 sourceCVE List V5
- VDB-343475 | Free5GC SMF PFCP UDP Endpoint handler.go HandlePfcpAssociationReleaseRequest null pointer dereferenceCVE reference · vdb-entry, technical-description
- VDB-343475 | CTI Indicators (IOB, IOC, IOA)CVE reference · signature, permissions-required
- Submit #739508 | free5gc SMF v4.1.0 Denial of ServiceCVE reference · third-party-advisory
- https://github.com/free5gc/free5gc/issues/794CVE reference · issue-tracking, exploit
- https://github.com/free5gc/smf/pull/188CVE reference · issue-tracking, patch
- https://github.com/free5gc/smf/CVE reference · product
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Improper Resource Shutdown or Release
Improper Resource Shutdown or Release represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.
NULL Pointer Dereference
NULL Pointer Dereference represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.