Skyvern through 1.0.56 contains a sandbox bypass vulnerability that allows authenticated users to execute code by
Source GCVE Database
Not known to be exploited · CVSS 8.7 High.
Data as of 6 Nov 2026, 16:50 UTC
Thin evidence
One scorer or none| CNA (VulnCheck) | CVSS 4.0 | 8.7 |
|---|---|---|
| CNA (VulnCheck) | CVSS 3.1 | 8.8 |
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 6 Nov 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 6 Nov 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Skyvern-AIskyvern | Affected
| Fixed in– |
PyPIskyvernpkg:pypi/skyvernOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Since Skyvern is not a cloud service, users should monitor the vendor's advisory for updates and apply any forthcoming patches promptly. Until a fix is released, restrict authenticated user privileges and consider additional access controls to limit exposure.
Description
Skyvern versions through 1.0.56 have a sandbox bypass vulnerability that allows authenticated users to execute arbitrary code on the server. This is achieved by reconstructing functions from raw bytecode using types.CodeType, enabling attackers to deploy scripts that evade the is_safe_script_code AST denylist and import restricted modules such as subprocess or socket. The vulnerability has a high severity with a CVSS score of 8.8.
References
- nvd.nist.gov/vuln/detail/CVE-2026-123783 (opens in a new tab)
- github.com/Skyvern-AI/skyvern/issues/8927 (opens in a new tab)
- github.com/Skyvern-AI/skyvern/pull/8937 (opens in a new tab)
- github.com/Skyvern-AI/skyvern/commit/31a64c1a4b5dfaf1e76a7164845e10f2d68248dc (opens in a new tab)
- github.com/Skyvern-AI/skyvern (opens in a new tab)
- github.com/Skyvern-AI/skyvern/blob/v1.0.56/skyvern/forge/sdk/workflow/code_block_safety.py (opens in a new tab)
- github.com/Skyvern-AI/skyvern/blob/v1.0.56/skyvern/forge/sdk/workflow/service.py (opens in a new tab)
- vulncheck.com/advisories/skyvern-through-1.0.56-script-sandbox-bypass-via-types-codetype-bytecode (opens in a new tab)