CVE-2026-21730
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedVerba is affected by a Stored Cross-Site Scripting (XSS) vulnerability within its login logging mechanism. When an unauthenticated remote attacker attempts to log in using an incorrect username and password combination, the supplied username value is recorded in the application logs. Due to lack of input sanitization, an attacker can inject a malicious XSS payload into the username field. This payload will be executed in the context of the administrator’s browser when the admin accesses the web application's log viewer. The vendor was notified early about this vulnerability, but didn't respond to our messages. This issue was fixed in version 10.0.6
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · high confidenceVerba logging mechanism stores unsanitized username input from failed login attempts. An unauthenticated remote attacker can inject XSS payloads into the username field during login, which executes when administrators view application logs in their browser.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data< 10.0.6CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Network
- Complexity
- Low
- Privileges
- None
- User interaction
- Required
- Scope
- Changed
- Confidentiality
- Low
- Integrity
- Low
- Availability
- None
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
-
Check the installed Verba versionLocate the Verba application version information in the platform admin interface or check the installed package version using the Verba version lookup method for your deploymentAffected if The installed version is lower than 10.0.6 (e.g., 10.0.5, 10.0.4, etc.)
-
Verify logging of failed login attempts is enabledAccess the Verba admin console and inspect the logging configuration settings for authentication events. Confirm that logging for failed login attempts is active.Affected if Failed login attempt logging is enabled and the version is below 10.0.6
-
Examine application logs for user-supplied dataNavigate to the Verba log viewing interface (typically accessible via the admin portal) and review logs that display username input from authentication eventsAffected if Logs display raw username input from login attempts without sanitization and the version is below 10.0.6
-
Review log access controlsCheck the admin interface permissions to determine which users can access the application log viewerAffected if Administrators can view logs through the web browser and the version is below 10.0.6
You are affected if the installed Verba version is below 10.0.6 and the application logging of failed login attempts is enabled, allowing unsanitized username input to be stored and rendered when administrators view logs.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
dbcve · scoped10.0.6
Upgrade to Verba version 10.0.6 or later, which includes input sanitization for the username parameter in the login logging mechanism.
10.0.6
- Backup your current Verba installation and database before proceeding with the upgrade
- Download Verba version 10.0.6 or later from the official Verba vendor source
- Follow the vendor's documented upgrade procedure to apply the update to your Verba installation
- After upgrading, verify the version number reflects 10.0.6 or later
- Test the login functionality by attempting a login with a test username containing special characters to confirm input is now properly sanitized in the logs
- Verify the administrator can view application logs without any XSS execution
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation1.0 h
- Implementation2.0 h
- Testing2.0 h
- Review / QA1.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,664.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-21730 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2026-21730 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.
A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.
- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
- No weaponised exploit code, or anything meant to cause harm
- No spam, self-promotion, credentials, or personal data