CVE-2023-31145
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 · uneditedCollabora Online is a collaborative online office suite based on LibreOffice technology. This vulnerability report describes a reflected XSS vulnerability with full CSP bypass in Nextcloud installations using the recommended bundle. The vulnerability can be exploited to perform a trivial account takeover attack. The vulnerability allows attackers to inject malicious code into web pages, which can be executed in the context of the victim's browser session. This means that an attacker can steal sensitive data, such as login credentials or personal information, or perform unauthorized actions on behalf of the victim, such as modifying or deleting data. In this specific case, the vulnerability allows for a trivial account takeover attack. An attacker can exploit the vulnerability to inject code into the victim's browser session, allowing the attacker to take over the victim's account without their knowledge or consent. This can lead to unauthorized access to sensitive information and data, as well as the ability to perform actions on behalf of the victim. Furthermore, the fact that the vulnerability bypasses the Content Security Policy (CSP) makes it more dangerous, as CSP is an important security mechanism used to prevent cross-site scripting attacks. By bypassing CSP, attackers can circumvent the security measures put in place by the web application and execute their malicious code. This issue has been patched in versions 22.05.13, 21.11.9, and 6.4.27. Users are advised to upgrade. There are no known workarounds for this vulnerability.
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 confidenceReflected XSS vulnerability with full Content Security Policy bypass in Collabora Online when integrated with Nextcloud using the recommended bundle. The flaw allows injection of malicious scripts that execute in victim browser context, enabling trivial account takeover by bypassing CSP protections.
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< 6.4.27>= 21.06.2, < 21.11.9>= 22.05.0, < 22.05.13CVSS 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.
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Identify Collabora Online versionCheck the installed Collabora Online package version. In a Docker environment, run 'docker images' and look for the collabora/online image, then check the tag or run 'docker inspect <container_id> --format="{{.Config.Image}}"'. On direct installation, check the package manager output or the about page in the admin interface.Affected if The installed version falls outside the safe ranges: not 6.4.27 or later, not 21.11.9 or later, and not 22.05.13 or later (or any version between 21.06.2 and 21.11.8, or between 22.05.0 and 22.05.12).
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Confirm Nextcloud integrationVerify that Collabora Online is integrated with Nextcloud. Check the Nextcloud admin panel under the Office section, or inspect the Collabora Online configuration file (typically /etc/loolwsd/loolwsd.xml) for Nextcloud-related settings such as 'nextcloud' in the domain config.Affected if Collabora Online is integrated with Nextcloud using the recommended bundle; the advisory explicitly states this integration vector is required for the vulnerability to be exploitable.
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Inspect CSP headers on Collabora endpointsUse browser developer tools or curl to examine HTTP response headers from Collabora Online endpoints (such as /hosting/discovery or the main WOPI endpoint). Look for Content-Security-Policy headers in responses.Affected if The CSP headers are present but can be bypassed due to the vulnerability; this check confirms the attack surface exists but requires version verification to determine if the bypass is present.
A user is affected if they run any Collabora Online version below 6.4.27, between 21.06.2-21.11.8, or between 22.05.0-22.05.12, integrated with Nextcloud using the recommended bundle.
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 · scoped6.4.2721.11.922.05.13
Upgrade Collabora Online to versions 22.05.13, 21.11.9, or 6.4.27 or later. No workarounds exist; immediate patching is required given the trivial exploitability and full CSP bypass.
6.4.27, 21.11.9, or 22.05.13 (depending on your major version branch)
- Identify the currently installed Collabora Online version using your package manager or administration interface
- Back up your current Collabora Online configuration and data
- Upgrade Collabora Online to version 6.4.27 or higher, or version 21.11.9 or higher, or version 22.05.13 or higher using your package manager or installation method
- Restart the Collabora Online service after the upgrade
- Verify the upgrade was successful by checking the installed version
- Test that the Collabora Online application functions correctly after the upgrade
- Verify that the XSS vulnerability is no longer present by testing the affected endpoint
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation2.0 h
- Implementation3.0 h
- Testing3.0 h
- Review / QA2.0 h
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Free · runs locallyCheck whether your project pulls in CVE-2023-31145 — 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-2023-31145 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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- 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