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TI-2026-29043 Aliases CVE-2026-40249GHSA-gx38-8h33-pmxr

Improper check for unusual conditions in free5gc

Priority LOW 38CWE-636Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
—
Confidentiality · integrity · availability
None · Low · None
Fix status
No fix listed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and GitHub.

Summary

free5GC is an open-source implementation of the 5G core network. In versions 4.2.1 and below of the UDR service, the PUT handler for updating Policy Data notification subscriptions at /nudr-dr/v2/policy-data/subs-to-notify/{subsId} does not return after request body retrieval or deserialization errors. Although HTTP 500 or 400 error responses are sent, execution continues and the processor is invoked with a potentially uninitialized or partially initialized PolicyDataSubscription object. This fail-open behavior may allow unintended modification of existing Policy Data notification subscriptions with invalid or empty input, depending on downstream processor and storage behavior. A patched version was not available at the time of publication.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00321 25th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Total

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

Affected products

VendorProductAffected versionsFixed inStatusSource
free5gcfree5gcup to 4.2.1—No fix listedCNA
—github.com/free5gc/udr (Go)up to 1.4.2—No fix listedGHSA-gx38-8h33-pmxr
  • free5gc Vendorfree5gc Affected up to 4.2.1 Fixed in — No fix listed CNA
  • github.com/free5gc/udr (Go) Vendor— Affected up to 1.4.2 Fixed in — No fix listed GHSA-gx38-8h33-pmxr

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:free5gc:free5gc:*:*:*:*:*:*:*:*up to 4.2.1Vulnerablefree5gc
  • cpe:2.3:a:free5gc:free5gc:*:*:*:*:*:*:*:* Versions up to 4.2.1 Vulnerable ·free5gc

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-40249
  2. 2026-10-03 Alias added: GHSA-gx38-8h33-pmxr

References

Exploit 1

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