Security readout for executives and security teams
Plain-English summary
CVE-2026-27839 is a privacy issue in wger, an open-source fitness manager. Authenticated users could access another user’s private nutrition plan details by guessing or supplying record IDs. Exposed data may include caloric intake and macro breakdowns. This is not a system takeover issue, but it can expose sensitive health and dietary information.
Executive priority
Treat as a moderate privacy issue. Organizations hosting wger for multiple users should remediate promptly because private health-adjacent data may be exposed between accounts. It is less urgent than remote code execution, but important for trust and privacy obligations.
Technical view
wger versions up to and including 2.4 have an IDOR/CWE-639 flaw in three nutritional_values action endpoints. The endpoints use Model.objects.get(pk=pk), bypassing the user-scoped queryset. Any authenticated user can retrieve another user’s nutrition plan data by referencing an arbitrary primary key. The listed fix is commit 29876a1954fe959e4b58ef070170e81703dab60e.
Likely exposure
Exposure is limited to wger deployments on version 2.4 or earlier where users can authenticate. Risk is higher for public or multi-user instances because any authenticated account may access other users’ private dietary records.
Exploitation context
The source bundle does not report active exploitation, and KEV is false. Exploitation requires valid authentication but no user interaction. The impact described is confidentiality-only: private nutrition data disclosure, not modification or service disruption.
Researcher notes
The vulnerability is an authenticated IDOR caused by bypassing user-scoped querysets in nutritional_values action endpoints. Evidence identifies affected versions as up to and including 2.4 and points to a fixing commit. No public source in the bundle confirms exploitation in the wild or a specific patched release number.
Mitigation direction
- Identify all wger deployments and confirm their versions.
- Prioritize public or multi-user wger instances.
- Apply the vendor fix referenced in commit 29876a1954fe959e4b58ef070170e81703dab60e.
- Check the GitHub advisory for updated release or upgrade guidance.
- Review access logs for unusual nutritional_values object access patterns.
Validation and detection
- Confirm wger is not running version 2.4 or earlier.
- Verify the deployed code no longer uses raw pk lookup in affected endpoints.
- Confirm nutritional_values access is constrained to the authenticated user’s queryset.
- Review vendor advisory status before closing the issue.
- Document whether any exposed instance allowed untrusted user registration.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
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ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-639: Exact CWE lookup
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Open ATT&CK lookupCVE-2026-27839 mapping review
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Open ATT&CK lookup- Severity
- Medium
- CVSS
- 4.3 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N2.81.4Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
4.3MediumVector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/wger-project/wger/security/advisories/GHSA-g8gc-6c4h-jg86CVE reference · x_refsource_CONFIRM
- https://github.com/wger-project/wger/commit/29876a1954fe959e4b58ef070170e81703dab60eCVE reference · x_refsource_MISC
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Authorization Bypass Through User-Controlled Key
Authorization Bypass Through User-Controlled Key represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.