CVE-2026-33062 — nrf
Fix: free5gc/nrf@dac77d8CVE-2026-33062 is a CWE-284 vulnerability in github.com/free5gc/nrf. A fix is available for github.com/free5gc/nrf — see the affected versions and patch details below.
free5GC NRF Discovery EncodeGroupId Function Panics on Malformed group-id-list Parameter
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-33062.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Real-World Exposure
github.com/free5gc/nrfReal-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 Input Validation vulnerability leading to Denial of Service.
- Security Impact: A remote attacker can cause the NRF service to panic and crash by sending a crafted HTTP GET request with a malformed
group-id-listparameter. This results in complete denial of service for the NRF discovery service. - Functional Impact: The
EncodeGroupIdfunction attempts to access array indices [0], [1], [2] without validating the length of the split data. When the parameter contains insufficient separator characters, the code panics with "index out of range". - Affected Parties: All deployments of free5GC v4.0.1 using the NRF discovery service.
Patches
Yes, the issue has been patched.
The fix is implemented in PR free5gc/nrf#80 (commit: [add fix reference here]).
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 NRF API to trusted sources only.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/free5gc/nrf | all versions | 1.4.2go get github.com/free5gc/nrf@v1.4.2 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/free5gc/nrf, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/free5gc/nrf to 1.4.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-33062 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2026-33062 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2026-33062. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-33062 in your dependencies?
O3 Security finds CVE-2026-33062 across Go dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.