Vulnerability in Vercel Deepsec
CVE-2026-109375
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.
Published .
CVSS v3 metric
CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:N/I:H/A:N.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
References
- github.com/vercel-labs/deepsec/pull/46 (issue-tracking, patch)
- github.com/vercel-labs/deepsec/pull/47 (issue-tracking, patch)
- github.com/vercel-labs/deepsec/commit/c5a4e4220ece72aee67c2ea21f4340e65f673fc1 (patch)
- github.com/vercel-labs/deepsec (product)
- www.vulncheck.com/advisories/vercel-deepsec-before-1.1.17-arbitrary-file-write-… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-109375?
- CVE-2026-109375 is a medium-severity vulnerability in Vercel Deepsec, classified under Improper Link Resolution Before File Access. CVSS score: 6.1/10. Published 2026-10-12.
- How severe is CVE-2026-109375?
- Medium severity. CVSS v3 base score is 6.1 out of 10.