CVE-2021-33708
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 · uneditedDue to insufficient input validation in Kyma, authenticated users can pass a Header of their choice and escalate privileges.
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 · moderate confidenceIn Kyma, authenticated users can supply arbitrary HTTP headers due to insufficient input validation on the server side. This allows attackers to manipulate the request headers to escalate their privileges beyond what their authenticated account should permit.
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< 1.24CVSS 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
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
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.
-
Confirm Kyma installationRun 'kubectl get kyma -A' or check for 'kyma-system' namespace in the cluster. Alternatively, run 'kyma version' if the CLI is available.Affected if No Kyma installation is found in the cluster, then this CVE does not apply.
-
Identify installed Kyma versionRun 'kubectl get kyma -A -o jsonpath="{.items[*].status.version}"' or use 'kyma version' command. Compare the version number to 1.24.Affected if The installed Kyma version is less than 1.24.
-
Verify API Server accessibilityCheck if the Kyma API Server proxy is exposed: run 'kubectl get apirules -A' and examine whether unauthenticated or low-privilege authenticated users can access it.Affected if The API Server is exposed to authenticated users without strict header validation.
-
Inspect HTTP header handling configurationReview any Istio VirtualService or Gateway configurations in the Kyma cluster for custom header manipulation rules: 'kubectl get virtualservices -A -o yaml | grep -i header'.Affected if Custom header passing rules are defined that bypass standard validation.
-
Review authentication and authorization policiesExamine Kyma's OAuth2 or JWT issuer configurations: 'kubectl get authorizationpolicies -A' and check for policies that rely on user-supplied headers for privilege decisions.Affected if Authorization policies exist that process incoming HTTP headers for access control decisions.
If Kyma is installed and the version is below 1.24, and the API Server is accessible to authenticated users, the environment is likely affected by this privilege escalation via arbitrary HTTP headers.
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 data1.24
Server-side fix: implement strict validation and sanitization of all incoming HTTP headers before processing, and enforce proper authorization checks for any privilege-sensitive operations.
- Consultation6.0 h
- Implementation12.0 h
- Testing8.0 h
- Review / QA4.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $8,448.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-33708 — 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-2021-33708 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