CVE-2026-33063
highpriority · track · 30EPSS 0.007 · 52 %ileEUUSEPSS · scored 2026-10-28
free5GC is an open source 5G core network. free5GC AUSF prior to version 1.4.2 has is an Improper Null Check vulnerability leading to Denial of Service. All deployments of free5GC v4.0.1 using the AUSF UE authentication service (`/nausf-auth/v1/ue-authentications` endpoint) are affected. A remote attacker can cause the AUSF service to panic and crash by sending a crafted UE authentication request that triggers a nil interface conversion in the `GetSupiFromSuciSupiMap` function. This results in complete denial of service for the AUSF authentication service. The `GetSupiFromSuciSupiMap` function attempts to perform an interface conversion from `interface{}` to `*context.SuciSupiMap` without checking if the underlying value is nil. When `SuciSupiMap` is nil, the code panics with "interface conversion: interface {} is nil, not *context.SuciSupiMap". free5GC AUSF version 1.4.2 patches the issue. There is no direct workaround at the application level. The recommendation is to apply the provided patch or restrict access to the AUSF API to trusted sources only.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.6–8.7
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (3)
Products and version ranges known to be affected.
advisories (2)
Vendor and ecosystem advisories describing this.
- GHSA-4jrw-92fg-4jwxfree5GC AUSF UE Authentication Panic on Nil SuciSupiMap Interface Conversion2026-03-18ghsa · osvUS
**Impact** This is an Improper Null Check vulnerability leading to Denial of Service. - **Security Impact**: A remote attacker can cause the AUSF service to panic and crash by sending a crafted UE authentication request that triggers a nil interface conversion in the `GetSupiFromSuciSupiMap` function. This results in complete denial of service for the AUSF authentication service. - **Functional Impact**: The `GetSupiFromSuciSupiMap` function attempts to perform an interface conversion from `interface{}` to `*context.SuciSupiMap` without checking if the underlying value is nil. When `SuciSupiMap` is nil, the code panics with "interface conversion: interface {} is nil, not *context.SuciSupiMap". - **Affected Parties**: All deployments of free5GC v4.0.1 using the AUSF UE authentication service (`/nausf-auth/v1/ue-authentications` endpoint). **Patches** Yes, the issue has been patched. The fix is implemented in PR free5gc/ausf#52 (commit: [add specific commit hash if available]). 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 restrict access to the AUSF API to trusted sources only.
- GO-2026-4754free5GC AUSF UE Authentication Panic on Nil SuciSupiMap Interface Conversion in github.com/free5gc/ausf2026-03-23vendor · osvUS
free5GC AUSF UE Authentication Panic on Nil SuciSupiMap Interface Conversion in github.com/free5gc/ausf
also known as (5)
Other names and identifiers for this entity.
sources
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references (13)
External citations — patches, advisories, analysis.
- https://github.com/free5gc/ausf/commit/3b9ac4403c2756dc89a5ed3cdcefe688458588aacnnvd
- https://github.com/free5gc/ausf/pull/52cnnvd
- https://github.com/free5gc/ausf/releasesPatchcnnvd
- https://github.com/free5gc/free5gc/issues/778cnnvd
- https://github.com/free5gc/free5gc/security/advisories/GHSA-4jrw-92fg-4jwxcnnvd
- https://github.com/free5gc/ausf/commit/3b9ac4403c2756dc89a5ed3cdcefe688458588aaenisa_euvd
- https://github.com/free5gc/ausf/pull/52enisa_euvd
- https://github.com/free5gc/free5gc/issues/778enisa_euvd
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