Vulnerability in Bytedance Inc. Deerflow

CVE-2026-34430

ByteDance DeerFlow versions prior to commit 92c7a20 contain a sandbox escape vulnerability in bash tool handling that allows attackers to execute arbitrary commands on the host system by bypassing regex-based validation using shell features such as directory changes and relative paths. Attackers can exploit the incomplete shell semantics modeling to read and modify files outside the sandbox boundary and achieve arbitrary command execution through subprocess invocation with shell interpretation enabled.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.008 (55.0th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 55th percentile — 55.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-34430: held from 0.004 to 0.008.

EPSS over last 30 days · oldest: 0.004 · newest: 0.008 · change: +0.004

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-34430?
CVE-2026-34430 is a high-severity vulnerability in Bytedance Inc. Deerflow, classified under Incomplete List of Disallowed Inputs. CVSS score: 8.8/10. Published 2026-04-01.
How severe is CVE-2026-34430?
High severity. CVSS v3 base score is 8.8 out of 10.