Vulnerability · Published Feb 26, 2026 · Assigned by GitHub_M
CVE-2026-27837Dottie vulnerable to prototype pollution bypass via non-first path segments in set() and transform()
Medium 6.3
In plain English
A medium-severity prototype pollution in dottie.js from mickhansen. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 30% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
Dottie provides nested object access and manipulation in JavaScript. Versions 2.0.4 through 2.0.6 contain an incomplete fix for CVE-2023-26132. The prototype pollution guard introduced in commit `7d3aee1` only validates the first segment of a dot-separated path, allowing an attacker to bypass the protection by placing `__proto__` at any position other than the first. Both `dottie.set()` and `dottie.transform()` are affected. Version 2.0.7 contains an updated fix to address the residual vulnerability.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | node-dottie | no fix listed | DEBIAN-CVE-2026-27837 |
| Debian:13 | node-dottie | no fix listed | DEBIAN-CVE-2026-27837 |
| Debian:14 | node-dottie | 2.0.7+~2.0.7-1 | DEBIAN-CVE-2026-27837 |
| Ubuntu:24.04:LTS | node-dottie | no fix listed | UBUNTU-CVE-2026-27837 |
| Ubuntu:25.10 | node-dottie | no fix listed | UBUNTU-CVE-2026-27837 |
| Ubuntu:26.04:LTS | node-dottie | no fix listed | UBUNTU-CVE-2026-27837 |
| Ubuntu:26.10 | node-dottie | no fix listed | UBUNTU-CVE-2026-27837 |
| npm | dottie | 2.0.7 | GHSA-r5mx-6wc6-7h9w |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| mickhansen | dottie.js | >= 2.0.4, < 2.0.7 |
Weakness: CWE-1321 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L
References
- https://github.com/mickhansen/dottie.js/security/advisories/GHSA-r5mx-6wc6-7h9w x_refsource_CONFIRM
- https://github.com/mickhansen/dottie.js/commit/7e8fa1345a4b46325f0eab8d7aeb1c4deaefdb14 x_refsource_MISC
- https://github.com/advisories/GHSA-4gxf-g5gf-22h4 x_refsource_MISC