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NVD / CVE Program· CNA GitHub_M

CVE-2026-44323: free5GC: UDR nudr-dr DELETE amf-subscriptions panics on missing subsId when UE state exists (nil pointer dereference)

MediumCVSS 6.5 · v3.1—No exploit Fix available

Noroxi assessment

Priority: Monitor (action score 26/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.35% (FIRST EPSS).
  • Anyone who can reach it over the internet can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
  • Fixed version: free5gc free5gc 4.2.2.
  • Severity is disputed: the assigning authority (CNA) scores it 4.3, NVD 6.5.

Low priority for now. Upgrade to free5gc free5gc 4.2.2 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's UDR nudr-dr DELETE /subscription-data/{ueId}/{servingPlmnId}/ee-subscriptions/{subsId}/amf-subscriptions handler contains a nil-pointer dereference reachable from a single authenticated request, after one preparatory authenticated EE-subscription create. The handler checks _, ok = UESubsData.EeSubscriptionCollection[subsId] and sets a 404 problem-details on the miss path, but then continues to UESubsData.EeSubscriptionCollection[subsId].AmfSubscriptionInfos -- dereferencing the same missing entry instead of returning. Gin recovery converts the panic into HTTP 500, but the endpoint remains repeatedly panicable. This vulnerability is fixed in 4.2.2.

Published
May 27, 2026
Updated
Oct 14, 2026
EPSS
0.3% · 29th percentile

Report tools

JSON

Action score

26

Monitor

Low priority for now.

CVSS
26 / 40 · 6.5 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.3%

CISA SSVC decision

Exploitation
none
Automatable
no
Technical impact
partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
6.5
CNA · GitHub_M
4.3
2.2 point gap

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2026-44323

When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
free5gcfree5gc

Versions reported by the vendor

Affected version ranges reported by the assigning authority (GitHub_M). Independent of NVD's CPE analysis and usually ahead of it.

  • free5gc free5gc

    • < 4.2.2affected

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • free5gc free5gcbefore 4.2.2

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
Gogithub.com/free5gc/udrbefore 1.4.31.4.3

Same product

free5gc: all records

Other highest-scoring records for the same primary product.

  • CVE-2026-44330free5GC: NEF nnef-pfdmanagement API is unauthenticated; forged bearer tokens can read PFD data and create/delete PFD subscriptions
    40Plan
  • CVE-2026-44329free5GC: SMF UPI management interface lacks auth middleware; unauthenticated topology read/write requests reach handlers
    40Plan
  • CVE-2026-44327free5GC: NEF nnef-oam route group is unauthenticated; no-token requests reach the OAM handler
    40Plan

Published before and after this one in the same product

  • ← EarlierCVE-2026-44321May 27, 2026 · free5GC: SMF UPI POST /upi/v1/upNodesLinks exits the SMF process on overlapping UE pools (unauthenticated, reachable Fatalf)
    30Monitor
  • ← EarlierCVE-2026-44322May 27, 2026 · free5GC: NEF 3gpp-pfd-management PATCH applications/{appId} panics on UDR access failure due to nil ProblemDetails dereference
    30Monitor
  • Later →CVE-2026-44324May 27, 2026 · free5GC: UDR nudr-dr DELETE amf-subscriptions panics on missing UE state via nil interface type assertion (single authenticated request)
    26Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
free5gc free5gc4.2.2 · descriptionVendor (CNA)
Go:github.com/free5gc/udr1.4.3Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

  • CVE-2026-3306369 days apartfree5GC AUSF UE Authentication Panic on Nil SuciSupiMap Interface Conversion
    34Monitor
  • CVE-2026-443160 days apartfree5GC: PCF npcf-smpolicycontrol POST /sm-policies panics on downstream UDR/OpenAPI 404 via nil pointer dereference
    30Monitor
  • CVE-2026-443220 days apartfree5GC: NEF 3gpp-pfd-management PATCH applications/{appId} panics on UDR access failure due to nil ProblemDetails dereference
    30Monitor
  • CVE-2026-443170 days apartfree5GC: PCF npcf-policyauthorization POST /app-sessions panics on suppFeat=1 with missing AfRoutReq via nil pointer dereference
    26Monitor

Not on record for this CVE: EPSS history · researcher credit · public bounty program.

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • A low-privileged account is enough.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
none
Integrity
none
Availability
high · the service can be disrupted
Attack vector
Network
Attack complexity
Low
Privileges required
Low
User interaction
None
Scope
Unchanged
Confidentiality impact
None
Integrity impact
None
Availability impact
High

Weakness class (CWE)

CWE-476 · NULL Pointer Dereference

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

nvd-primary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

MITRE has no CAPEC/ATT&CK mapping for this CWE.

References

Show all references (1 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records