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Fencer Intel
high 7.2

CVE-2026-33881 json

Windmill: Rogue Workspace Admins can inject code via unescaped workspace environment variable interpolation in NativeTS executor

published 7mo ago modified 4mo ago also EUVD-2026-16820

cvss
7.2
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
0.4%
EPSS 0.4% chance of exploitation in 30 days, percentile 33%
public exploits
0
none known

Summary

Windmill is an open-source developer platform for internal code: APIs, background jobs, workflows and UIs. Workspace environment variable values are interpolated into JavaScript string literals without escaping single quotes in the NativeTS executor. A workspace admin who sets a custom environment variable with a value containing `'` can inject arbitrary JavaScript that executes inside every NativeTS script in that workspace. This is a code injection bug in `worker.rs`, not related to the sandbox/NSJAIL topic. Version 1.664.0 patches the issue.

Patch / fix

  • windmill windmill 1.664.0

Is CVE-2026-33881 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

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CISA SSVC

Exploitation
Proof of concept is public
Automatable
no
Technical impact
total
Assessed
7mo ago

Exploit prediction

0.39% chance of exploitation in the next 30 days, higher than 33% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • github.com https://github.com/windmill-labs/windmill/security/advisories/GHSA-8q8j-mm3g-5c2q referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 4.0 7.3 CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P
CNA 4.0 7.3 CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
NVD 3.1 7.2 CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H

Affected products

  • windmill-labs windmill

Classification

Weakness
  • CWE-94 Improper Control of Generation of Code

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.