CVE-2026-52783
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 · uneditedOpenProject is open-source, web-based project management software. Prior to 17.3.3 and 17.4.1, OpenProject's Storages module writes the OneDrive/SharePoint userless OAuth access_token plaintext to Rails.cache under the deterministic key storage.<id>.httpx_access_token, repopulated continuously by an hourly cron and every userless-OAuth call site (see Write cadence). None of the three allowed cache backends (file_store, memcache, redis) encrypts at rest. An attacker with read access to the cache backend recovers the Azure-AD application-tier bearer with an anonymous get over the memcached binary protocol (or the equivalent against Redis). This vulnerability is fixed in 17.3.3 and 17.4.1.
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 confidenceOpenProject's Storages module stores OneDrive/SharePoint userless OAuth access tokens in plaintext in Rails.cache under deterministic keys (storage.<id>.httpx_access_token), with no encryption at rest across file_store, memcache, and redis backends. An attacker with read access to the cache backend can retrieve the Azure-AD application-tier bearer token via the memcached binary protocol or equivalent Redis query.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
CVSS 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
- High
- Privileges
- Low
- User interaction
- None
- Scope
- Changed
- Confidentiality
- High
- Integrity
- High
- Availability
- None
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/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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Confirm OpenProject installation and versionLocate the OpenProject installation and identify its version by checking the installed package or application metadata. Compare the version against the fixed releases (17.3.3 or 17.4.1).Affected if OpenProject version is below 17.3.3 or 17.4.1 and the Storages module is in use.
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Verify the Storages module is enabledAccess the OpenProject administration panel and check if the Storages module (OneDrive/SharePoint integration) is enabled in the project or global settings.Affected if The Storages module is enabled and configured for OneDrive or SharePoint integrations.
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Identify configured OneDrive/SharePoint storagesIn the OpenProject administration under Storage settings, enumerate any configured OneDrive or SharePoint storage entries that use userless OAuth (application-tier tokens).Affected if Any OneDrive or SharePoint storage connections are configured with application-tier OAuth tokens.
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Determine the Rails.cache backendExamine the OpenProject configuration files (typically config/configuration.yml or environment config) to identify which cache store is configured: file_store, memcache, or redis.Affected if The cache backend is file_store, memcache, or redis without encryption at rest enabled.
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Inspect cache contents for plaintext tokensQuery the cache backend directly: for Redis use KEYS or GET commands for patterns like 'storage.*.httpx_access_token'; for memcached use get commands for equivalent keys; for file_store examine the cache files directly.Affected if Cache entries contain plaintext bearer tokens under keys matching 'storage.<id>.httpx_access_token'.
A user is affected if running a vulnerable OpenProject version with the Storages module enabled and OneDrive/SharePoint configured, using an unencrypted cache backend where plaintext OAuth tokens are discoverable.
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 · scopedUpgrade to OpenProject version 17.3.3 or 17.4.1 to receive the vendor patch. Additionally, implement encryption at rest for cache backends and rotate exposed Azure-AD application credentials as a precaution.
OpenProject 17.3.3 or 17.4.1 (both contain the fix)
- 1. Back up your current OpenProject database and configuration files
- 2. Consult OpenProject upgrade documentation for your deployment method (Docker, package, or source)
- 3. Upgrade to version 17.3.3 or 17.4.1 (either version contains the fix)
- 4. After upgrade, verify the Storages module functions correctly with OneDrive/SharePoint integrations
- 5. If using memcached or Redis as cache backend, consider rotating the OAuth tokens/Credentials that were previously stored in plaintext as a precaution
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation4.0 h
- Implementation12.0 h
- Testing6.0 h
- Review / QA3.0 h
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Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-52783 — 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-2026-52783 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