How severe is CVE-2026-33065?

No CVSS score has been assigned to CVE-2026-33065 yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by CVE-2026-33065?

CVE-2026-33065 affects the following packages: github.com/free5gc/udm (Go). Ecosystems affected: Go.

How do I fix CVE-2026-33065?

Update github.com/free5gc/udm to 1.4.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-33065 is resolved across your whole dependency graph.

How do I detect CVE-2026-33065 in my Go dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/free5gc/udm, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2026-33065 if there is no patch (or I can't update yet)?

Assume what was exposed is already known: rotate any credential, token or key that the affected component could return, restrict the endpoint to callers that genuinely need it, and strip sensitive fields from responses and error output at the boundary rather than relying on the client not to read them.

Is CVE-2026-33065 actively exploited in the wild?

No public exploit code has been indexed for CVE-2026-33065 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2026-33065?

CVE-2026-33065 has an EPSS (Exploit Prediction Scoring System) score of 0.3%, placing it in the 21th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2026-33065?

CVE-2026-33065 is classified as CWE-209 (CWE-209). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2026-33065 published, and has it been updated?

CVE-2026-33065 was published on March 20, 2026 and was last updated on October 28, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐹 Go

Not in CISA KEV

CVE-2026-33065 — udm

Fix: free5gc/udm@88de9fa

CVE-2026-33065 is a CWE-209 vulnerability in github.com/free5gc/udm. A fix is available for github.com/free5gc/udm — see the affected versions and patch details below.

free5GC UDM incorrectly returns 500 for empty supi path parameter in DELETE sdm-subscriptions request

Also known asGHSA-958m-gxmc-mccmGO-2026-4758

Published

Mar 20, 2026

Updated

Oct 28, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Nov 5, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

Proof-of-concept exploit code exists

CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.

Exploitation and automatability from CISA’s SSVC triage for CVE-2026-33065.

EPSS Exploitation Probability

via FIRST.org ↗

0.3%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs21th percentile — riskier than 21% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

Real-World Exposure

1 pkg affected

🐹github.com/free5gc/udm

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.

Description

Impact
This is an Improper Error Handling vulnerability with Information Exposure implications.

Security Impact: The UDM incorrectly converts a downstream 400 Bad Request (from UDR) into a 500 Internal Server Error when handling DELETE requests with an empty supi path parameter. This leaks internal error handling behavior and makes it difficult for clients to distinguish between client-side errors and server-side failures.
Functional Impact: When a client sends a DELETE request with an empty supi (e.g., double slashes // in URL path), the UDM forwards the malformed request to UDR, which correctly returns 400. However, UDM propagates this as 500 SYSTEM_FAILURE instead of returning the appropriate 400 error to the client. This violates REST API best practices for DELETE operations.
Affected Parties: All deployments of free5GC v4.0.1 using the UDM Nudm_SDM service with DELETE operations on sdm-subscriptions endpoint.

Patches
Yes, the issue has been patched.
The fix is implemented in PR free5gc/udm#79.
Users should upgrade to the next release of free5GC that includes this commit.

Workarounds
There is no direct workaround at the application level. The recommendation is to apply the provided patch or implement API gateway-level validation to reject DELETE requests with empty path parameters before they reach UDM.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🐹Go	`github.com/free5gc/udm`	all versions	1.4.2`go get github.com/free5gc/udm@v1.4.2`

Affected Products

1 product · 1 configurations

Application

udmfree5gc

< 1.4.2

range

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/free5gc/udm, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/free5gc/udm to 1.4.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-33065 is resolved across your whole dependency graph.
Workarounds
Assume what was exposed is already known: rotate any credential, token or key that the affected component could return, restrict the endpoint to callers that genuinely need it, and strip sensitive fields from responses and error output at the boundary rather than relying on the client not to read them.

Frequently Asked Questions

**Impact** This is an Improper Error Handling vulnerability with Information Exposure implications. - **Security Impact**: The UDM incorrectly converts a downstream 400 Bad Request (from UDR) into a 500 Internal Server Error when handling DELETE requests with an empty `supi` path parameter. This leaks internal error handling behavior and makes it difficult for clients to distinguish between client-side errors and server-side failures. - **Functional Impact**: When a client sends a DELETE request with an empty `supi` (e.g., double slashes `//` in URL path), the UDM forwards the malformed

O3 Security · Impact-Aware SCA

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