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TI-2026-32286 Aliases CVE-2026-44318GHSA-27ph-8q4f-h7m7

Race condition in free5gc

Priority MEDIUM 62CWE-362Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
None · None · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub.

Summary

free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's BSF PUT /nbsf-management/v1/subscriptions/{subId} handler has an unsynchronized write on the global Subscriptions map. The handler first reads the map under RLock() via BSFContext.GetSubscription(subId), but if the subscription does not exist, ReplaceIndividualSubcription() writes back to the same map directly without taking the mutex (bsfContext.BsfSelf.Subscriptions[subId] = subscription). Under concurrent authenticated PUT load, one goroutine can read while another writes the map, which causes the Go runtime to abort the process with fatal error: concurrent map read and map write (Go runtime panics that come from concurrent map access bypass recover() and terminate the process). The BSF container exits with code 2 -- the entire BSF SBI surface goes down until restart. This vulnerability is fixed in 4.2.2.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00332 26th percentileScored 2026-11-07
Public exploit Yes 2 exploit referencesTagged by NVD
Fix Fixed free5gc (free5gc): 4.2.2github.com/free5gc/bsf (Go): 1.0.2

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
free5gcfree5gcbefore 4.2.24.2.2Patch availableCNA
—github.com/free5gc/bsf (Go)before 1.0.21.0.2Patch availableGHSA-27ph-8q4f-h7m7
  • free5gc Vendorfree5gc Affected before 4.2.2 Fixed in 4.2.2 Patch available CNA
  • github.com/free5gc/bsf (Go) Vendor— Affected before 1.0.2 Fixed in 1.0.2 Patch available GHSA-27ph-8q4f-h7m7

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:free5gc:free5gc:*:*:*:*:*:*:*:*before 4.2.2Vulnerablefree5gc
  • cpe:2.3:a:free5gc:free5gc:*:*:*:*:*:*:*:* Versions before 4.2.2 Vulnerable ·free5gc

Remediation

  • Fix · CNA free5gc (free5gc) Fixed in 4.2.2
  • Fix · GHSA-27ph-8q4f-h7m7 github.com/free5gc/bsf (Go) Fixed in 1.0.2 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-44318
  2. 2026-10-03 Alias added: GHSA-27ph-8q4f-h7m7

References

Exploit 2

Patch 2

Advisory 1

Other 1

  • TI-2026-32298 Incorrect authorization in free5gc CVSS 3.1CRITICAL 10.0
  • TI-2026-32297 free5GC: SMF UPI management interface lacks auth middleware; unauthenticated topology read/write requests reach handlers CVSS 3.1CRITICAL 10.0
  • TI-2026-32295 free5GC: NEF nnef-oam route group is unauthenticated; no-token requests reach the OAM handler CVSS 3.1CRITICAL 10.0
  • TI-2025-39412 free5gc v4.1.0 and before is vulnerable to Buffer Overflow. CVSS 3.1CRITICAL 9.8
  • TI-2026-32294 Missing authorization in free5gc CVSS 3.1CRITICAL 9.4
  • TI-2026-32283 Missing authorization in free5gc CVSS 3.1CRITICAL 9.4
See all 58 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences