Link following in open-multi-agent file_write escapes sandbox
Key facts
- Attack vector
- Local
- Privileges required
- None
- User interaction
- Passive
- Attack complexity
- Low
- Attack requirements
- Present
- Impact type
- —
- Confidentiality · integrity · availability
- None · High · None
- Fix status
- No fix listed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA.
Summary
The open-multi-agent package (@open-multi-agent/core) from 1.5.0 through 1.21.2 contains a link following flaw in its file_write tool sandbox. The tool follows dangling symlinks, which lets files be created outside the workspace root (CWE-59). A local attacker who can plant a dangling symlink in the workspace can use prompt injection, with user interaction, to steer the agent into writing attacker-influenced content anywhere the agent process can write.
Written with Claude Haiku 5.5 from the sources below · 2026-10-29
Description from the CNA
open-multi-agent (@open-multi-agent/core) 1.5.0 through 1.21.2 contains a link following vulnerability in the file_write tool sandbox that allows attackers to create files outside the workspace root by using dangling symlinks. Attackers can plant a dangling symlink in the workspace and steer the agent via prompt injection to write attacker-influenced content anywhere the agent process can write.
Why it matters now
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
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| open-multi-agent | open-multi-agent | 1.5.0 – 1.21.2 | — | No fix listed | CNA |
- open-multi-agent Vendoropen-multi-agent Affected 1.5.0 – 1.21.2 Fixed in — No fix listed CNA
Remediation
The sources list no fixed version for open-multi-agent.
Written with Claude Haiku 5.5 from the sources below · 2026-10-29
Timeline
- 2026-10-11 Threatist record created from CVE-2026-108600
- 2026-10-11 Alias added: GHSA-h42w-g3ch-rjjm
- 2026-10-11 Priority changed: MEDIUM → LOW
- 2026-10-13 CISA SSVC decision points changed
- 2026-10-13 Priority changed: LOW → MEDIUM
References
Other 3
- https://github.com/open-multi-agent/open-multi-agent/blob/6ec5498643c7e431aa66751f17f47a529e7f927c/packages/core/src/tool/built-in/path-safety.ts#L104-L113
- https://github.com/open-multi-agent/open-multi-agent/blob/6ec5498643c7e431aa66751f17f47a529e7f927c/packages/core/src/tool/built-in/file-write.ts#L67
- https://github.com/open-multi-agent/open-multi-agent
Sources
- CVE-2026-108600 · CVE Program
- CVE-2026-108600 · NVD
- FIRST EPSS
- GHSA-h42w-g3ch-rjjm · GitHub Advisory Database · CC BY 4.0
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