CVE-2021-21435
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 · uneditedArticle Bcc fields and agent personal information are shown when customer prints the ticket (PDF) via external interface. This issue affects: OTRS AG OTRS 7.0.x version 7.0.23 and prior versions; 8.0.x version 8.0.10 and prior versions.
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 confidenceAn information disclosure vulnerability in OTRS allows sensitive data (Bcc fields from email articles and agent personal information) to be exposed in PDF documents generated through the customer-facing external interface. This occurs because the PDF generation logic for the external interface does not properly filter these fields.
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>= 6.0.0, <= 6.0.30>= 7.0.0, <= 7.0.23>= 8.0.0, <= 8.0.10CVSS 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
- Unchanged
- Confidentiality
- High
- Integrity
- None
- Availability
- None
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/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.
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Determine installed OTRS versionCheck the version file in the OTRS installation directory, typically found in Kernel/Config.pm or by running 'bin/otrs.Console.pl Admin::Config::Read --Key "Version"' from the OTRS home directoryAffected if The installed version falls within 6.0.0-6.0.30, 7.0.0-7.0.23, or 8.0.0-8.0.10
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Verify external customer interface is enabledCheck the OTRS system configuration setting 'CustomerPanel::Enabled' in Admin > System Configuration, or inspect the Config.pm file for '$Self->{'CustomerPanel'}->{Enabled} = 1'Affected if The customer-facing external interface is enabled and accessible to unauthenticated or authenticated customers
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Confirm PDF generation is accessible via external interfaceCheck if the CustomerTicketZoom action or PDF download functionality is available in the external customer portal by reviewing the frontend module registration in Kernel/Config.pmAffected if Customers can generate or download PDF documents from the external interface
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Inspect PDF generation configuration for filteringReview the PDF configuration in Admin > System Configuration, specifically settings related to 'PDF' and 'Article' to see if Bcc field filtering or agent PII masking is explicitly configuredAffected if No custom filters or masking configurations are present in the PDF generation settings
You are affected if your OTRS version is within the vulnerable ranges AND the external customer interface with PDF generation capability is enabled without custom filters in place.
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.
From vendor dataUpgrade OTRS to version 7.0.24 or later, or 8.0.11 or later. Alternatively, implement a custom filter in the PDF generation code to exclude Bcc fields and mask agent PII from external-facing ticket PDFs.
- Consultation3.0 h
- Implementation6.0 h
- Testing4.0 h
- Review / QA2.0 h
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Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-21435 — 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-2021-21435 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
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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