CVE-2026-68746 is a high severity (CVSS 8.8) authentication flaw in Livebook, the Elixir notebook server. When a deployment group cannot be resolved, Teams identity checks fail open and an unauthenticated client gets full access. Versions 0.19.7 up to 0.19.9 are affected. Upgrade to 0.19.9.
What's affected
The record says Livebook is affected from 0.19.7 before 0.19.9. The Erlang Ecosystem Foundation CNA entry I retrieved agrees: 0.19.7 up to but not including 0.19.9, and every other version unaffected. The fix is 0.19.9.
Severity differs. The record scores it 8.8 (High). The CNA entry rates it High 7.7 using CVSS 4.0. Both are High.
The condition is specific. It applies to a Livebook Agent or App Server connected to Livebook Teams with identity enforcement. The cached deployment group identifier becomes unresolvable when the group is deleted while the agent is disconnected or reconnecting. Servers that do not use Teams identity enforcement are outside the description.
How to check if you're exposed
mix deps | grep livebook
grep livebook mix.lock
The lock file records the exact resolved version, so check it rather than the version range in mix.exs.
For Docker deployments, check the image tag you run:
docker ps --format "table {{.Names}}\t{{.Image}}"
Then check whether your server uses Livebook Teams with identity enforcement. If it does and the version is between 0.19.7 and 0.19.8, upgrade now, and check whether any deployment group was deleted while an agent was offline.
A quicker route for a whole project is the free in-browser dependency scan at Gold. Paste a manifest or lockfile and it matches each dependency against known CVEs, including ones pulled in indirectly.
What to do now
- Upgrade Livebook to 0.19.9 or later, including container images and any app servers deployed from them.
- Do not expose Livebook servers directly to the internet. Put them behind a network control that does not depend on the application's own identity check.
- If you use Teams identity enforcement, review recent deployment group deletions and agent reconnects.
- Assume secrets configured on an affected server may have been readable, and rotate those you cannot account for.
- Review server logs for access from unknown clients during the period you ran an affected version.
Reachability analysis helps with ordering the work. Knowing whether your code actually calls the affected path tells you which services to patch first.
Why it matters
The weakness is CWE-636, not failing securely. The code that decides whether identity enforcement is on handled one case, a group found with enforcement enabled, and reported "off" for everything else, including a group it could not find at all. Neighbouring functions treated the same unresolved result as a denial.
When enforcement looked off, the request carried on and the user defaulted to full access. The record says full access includes reading notebooks and configured secrets and running code on the server's runtime. The rule is old and simple: when a security check cannot get its answer, deny. The record does not mark this CVE as known exploited.
Try it yourself
This demo shows how to spot findings where a fixed version already exists, so upgrades like this one go to the top of the queue.
Click through it at your own pace, or open it full screen.
Quick check
Are all Livebook servers affected?
The record describes servers that enforce identity through Livebook Teams, in versions 0.19.7 up to 0.19.9.
What can an attacker do?
Per the record, the access of a fully privileged member, including reading notebooks and secrets and executing code on the runtime.
Sources
- https://cna.erlef.org/cves/CVE-2026-68746.html
- Record: NVD entry for CVE-2026-68746 (score 8.8, HIGH)
Last reviewed: 18 October 2026.
