CVE-2025-3197 json
expand-object Vulnerable to Prototype Pollution via the expand() Function
published 2025-04-04 19 mo ago modified 2026-06-17 4 mo ago also GHSA-4vjr-hfpp-2m7w , EUVD-2025-9700
- cvss
- 7.3
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.4%
- EPSS 0.4% chance of exploitation in 30 days, percentile 36%
- public exploits
- 0
- none known
Summary
Versions of the package expand-object from 0.0.0 are vulnerable to Prototype Pollution in the expand() function in index.js. This function expands the given string into an object and allows a nested property to be set without checking the provided keys for sensitive properties like __proto__.
CISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 19 mo ago
Exploit prediction
0.42% chance of exploitation in the next 30 days, higher than 36% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- security.snyk.io https://security.snyk.io/vuln/SNYK-JS-EXPANDOBJECT-5821390 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 6.9 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P |
| CNA | 3.1 | 7.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L |
| CNA | 4.0 | 5.5 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/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 |
| GitHub | 3.1 | 7.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| npm | expand-object | <=0.4.2 |
no fix listed |
Affected products
- n/a expand-object
Classification
- Weakness
-
- CWE-1321 Improperly Controlled Modification of Object Prototype Attributes
References
-
security.snyk.io
/vuln/SNYK-JS-EXPANDOBJECT-5821390
exploit, web
-
gist.github.com
/miguelafmonteiro/d8f66af61d14e06338b688f90c4dfa7c
web
- github.com /jonschlinkert/expand-object/blob/master/index.js%23L13
-
nvd.nist.gov
/vuln/detail/CVE-2025-3197
advisory
-
github.com
/jonschlinkert/expand-object
package
-
github.com
/jonschlinkert/expand-object/blob/master/index.js#L13
web
Sources
- CVE List CVE-2025-3197
- GitHub Advisory GHSA-4vjr-hfpp-2m7w
- NVD CVE-2025-3197
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