What’s Vulnerable › Vulnerabilities

CVE-2026-109375: Vercel deepsec before 1.1.17 Arbitrary File Write via Symlink in Sandbox Tarball Extraction

• Severity: medium (CVSS 6.1 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.3% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-10-12 · updated 2026-10-16
• Weakness: CWE-59

Description

Vercel deepsec from 0.1.0 before 1.1.17 contains a link following vulnerability in extractTarballLocally that allows sandboxed code to write files outside the sandbox by planting links in result tarballs. Attackers controlling sandbox code, such as a prompt-injected coding agent, can plant symbolic or hard links in the host data directory to write arbitrary files on the orchestrator host.

Affected products

• Vercel deepsec: from 0.1.0 before 1.1.17 — fixed in 1.1.17

How to fix

Upgrade to a fixed version: Vercel deepsec 1.1.17. Check the vendor advisory for mitigations.

References

• https://github.com/vercel-labs/deepsec
• https://github.com/vercel-labs/deepsec/commit/c5a4e4220ece72aee67c2ea21f4340e65f673fc1
• https://github.com/vercel-labs/deepsec/pull/46
• https://github.com/vercel-labs/deepsec/pull/47
• https://www.vulncheck.com/advisories/vercel-deepsec-before-1.1.17-arbitrary-file-write-via-symlink-in-sandbox-tarball-extraction

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