CVE-2021-41242
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 · uneditedOpenOlat is a web-basedlearning management system. A path traversal vulnerability exists in OpenOlat prior to versions 15.5.12 and 16.0.5. By providing a filename that contains a relative path as a parameter in some REST methods, it is possible to create directory structures and write files anywhere on the target system. The attack could be used to write files anywhere in the web root folder or outside, depending on the configuration of the system and the properly configured permission of the application server user. The attack requires an OpenOlat user account, an enabled REST API and the rights on a business object to call the vulnerable REST calls. The problem is fixed in version 15.5.12 and 16.0.5. There is a workaround available. The vulnerability requires the REST module to be enabled. Disabling the REST module or limiting the REST module via some firewall or web-server access rules to be accessed only be trusted systems will mitigate the risk.
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 analysisA detailed technical summary for this CVE is being prepared.
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< 15.5.12>= 16.0.0, < 16.0.5CVSS 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
- None
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H
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 · scoped15.5.1216.0.5
15.5.12 for 15.x branch; 16.0.5 for 16.x branch
- 1. Identify current OpenOlat version by checking the admin interface or version file
- 2. If running version 15.x.x (< 15.5.12): plan upgrade to version 15.5.12 or later
- 3. If running version 16.x.x (>= 16.0.0 and < 16.0.5): plan upgrade to version 16.0.5 or later
- 4. Backup the current OpenOlat installation and database before upgrading
- 5. Follow OpenOlat upgrade documentation to apply the update
- 6. After upgrade, verify the REST module is properly configured and consider restricting access if not needed
Generated from the published advisory — verify against the referenced sources before acting.
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Free · runs locallyCheck whether your project pulls in CVE-2021-41242 — 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-2021-41242 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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- Version or environment caveats, and links to real fixes
- No weaponised exploit code, or anything meant to cause harm
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