CVE-2026-77104 is a high severity (7.5) path traversal in Commvault CommServe that affects information disclosure. Commvault's fix is a maintenance release: 11.46.20, 11.44.20, 11.40.72 or 11.36.123, or higher. Update CommServe.
What's affected
The advisory title is "CommServe Path Traversal". Commvault says CommServe contained a path traversal issue affecting information disclosure.
Commvault's advisory lists these affected versions on Linux and Windows, with the first resolved version for each:
- 11.46.0 to 11.46.19, resolved in 11.46.20 and higher
- 11.44.0 to 11.44.19, resolved in 11.44.20 and higher
- 11.40.0 to 11.40.71, resolved in 11.40.72 and higher
- 11.36.0 to 11.36.122, resolved in 11.36.123 and higher
Commvault says supported versions not listed are unaffected, and unsupported versions must be upgraded.
Where sources differ. Commvault's advisory lists a CVSS score of 8.3 and does not state the scoring version on the page. The record's score is 7.5 and Commvault's is 8.3. Severity is High in both, and the fixed versions come from the advisory.
How to check if you're exposed
Commvault gives a way to confirm updates. Log in to Command Center, go to Manage, then Servers (or Manage, Infrastructure, Servers on newer builds), filter servers by role such as the Web Server role, and confirm every server shows the resolved maintenance release or a higher one.
Do this per server, not per environment. The advisory names which component needs the update: CommServe. Servers that are offline, in a lab or at a remote site are the ones that get missed.
What to do now
- Upgrade to a resolved maintenance release: 11.46.20, 11.44.20, 11.40.72 or 11.36.123, or higher in your line.
- Update the component named in the advisory: CommServe.
- Confirm the update from Command Center under Manage, then Servers.
- If you run an unsupported version, plan an upgrade to a supported one, since Commvault says unsupported versions must be upgraded.
- Limit network access to Commvault services to the hosts that need it while updates roll out.
Why it matters
Path traversal lets a caller steer file access outside the intended folder, and it is filed under CWE-22. Commvault says the effect is information disclosure, and the record's vector shows network access, no privileges and high confidentiality impact.
Together with the authentication bypass fixed in the same release, this means several CommServe issues can reveal information without credentials. That raises the value of checking exposure of the CommServe network port to hosts that do not need it. The record does not mark it as a CISA KEV entry.
Quick check
What kind of data could be exposed?
Commvault's summary says information disclosure and gives no list. Treat configuration and catalog data as sensitive until you have patched.
Which release fixes it?
11.46.20, 11.44.20, 11.40.72 or 11.36.123, or higher in the matching line.
Sources
Last reviewed: 18 October 2026.
