← back
CVE-2026-34213

Docmost has cross-page attachment overwrite via flawed attachmentId overwrite validation

CVSS 5.4 MEDIUMEPSS 0.2%CWE-639
Vexday Risk Score
33Attention
SSVC decision (CISA)
Attend
PoC available → attend closely
CVSS 5.4EPSS 0.2%KEV nãoPoC públicaNuclei Metasploit Patch
Lifecycle
14 Apr 2026Published on NVD
26 Jun 2026Public PoC
Recommendation: Plan a near-term fix — a public PoC already exists.
Docmost is open-source collaborative wiki and documentation software. Starting in version 0.3.0 and prior to version 0.71.0, improper authorization in Docmost allows a low-privileged authenticated user to overwrite another page's attachment within the same workspace by supplying a victim `attachmentId` to `POST /api/files/upload`. This is a remote integrity issue requiring no victim interaction. Version 0.71.0 contains a patch.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L
Affected products
docmost · docmost
⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.

Want to know if your infrastructure is exposed to this?

Talk to TrueHacking →