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TI-2026-59070 Aliases CVE-2026-86285GHSA-9rg8-hwc3-hh5g

BookStack Attachment Edit Endpoint AttachmentController.php getUpdateForm access control

Priority MEDIUM 57CWE-266Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Privilege escalation, Security bypass
Confidentiality · integrity · availability
Low · None · None
Fix status
No fix listed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-266 and CWE-284.

Summary

A vulnerability was detected in BookStack up to 26.05.2. Affected by this issue is the function AttachmentController::getUpdateForm of the file app/Uploads/Controllers/AttachmentController.php of the component Attachment Edit Endpoint. The manipulation of the argument ID results in improper access controls. The attack may be launched remotely. The exploit is now public and may be used. The patch is identified as 4e406c41c4c8060a5795e74c66fb96362e54f400. It is advisable to implement a patch to correct this issue.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00385 32nd percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by the CNA
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
—BookStack26.05.0; 26.05.1; 26.05.2—No fix listedCNA
  • BookStack Vendor— Affected 26.05.0; 26.05.1; 26.05.2 Fixed in — No fix listed CNA

CPE names CNA · 1

CPEVersionsRoleVendor
cpe:2.3:a:bookstack:bookstack:*:*:*:*:*:*:*:*———
  • cpe:2.3:a:bookstack:bookstack:*:*:*:*:*:*:*:* Versions — — ·—

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-86285
  2. 2026-10-03 Alias added: GHSA-9rg8-hwc3-hh5g

References

Exploit 1

Patch 1

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences