CVE-2026-85625
sift (sift.js) 17.1.3 enumerates query keys with for...in, which walks the object prototype chain, and dispatches any matched operator key including $where. The $where operation compiles a string value into a function using new Function unless CSP_ENABLED is set (not set by default). As a result, if a prototype-pollution primitive elsewhere in the process sets Object.prototype.$where to a malicious string, even benign filter calls such as sift({}) execute arbitrary JavaScript. Additionally, passing an untrusted query object containing a string $where directly to sift results in code execution under the default configuration.
What this means for your business
- An attacker can use it remotely, over a network, without a login, and without anyone at your company clicking anything.
- FIRST's prediction model gives it a 0.5% chance of attack attempts being seen in the next 30 days, ranking above 44% of all known flaws.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
Not sure if your company is exposed?
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Scoring
- CVSS
- 8.1 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H- CVSS v4
- 9.2
- Weakness
- CWE-1321
- Assigned by
- disclosure@vulncheck.com
Dates
- Published
- 2026-09-04
- Last modified
- 2026-09-14
- Sources
- NVD