CVE-2021-23700 json
Prototype Pollution
published 2021-12-10 4 y ago modified 2026-06-17 4 mo ago also GHSA-j28q-p8ww-cp87 , EUVD-2021-2536
- cvss
- 6.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.2%
- EPSS 1.2% chance of exploitation in 30 days, percentile 68%
- public exploits
- 0
- none known
Summary
All versions of package merge-deep2 are vulnerable to Prototype Pollution via the mergeDeep() function.
Exploit prediction
1.21% chance of exploitation in the next 30 days, higher than 68% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- snyk.io https://snyk.io/vuln/SNYK-JS-MERGEDEEP2-1727593 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 6.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L/E:P |
| CNA | 3.1 | 6.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L |
| NVD | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| NVD | 2.0 | 7.5 | AV:N/AC:L/Au:N/C:P/I:P/A:P |
| GitHub | 3.1 | 6.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| npm | merge-deep2 | <=3.0.6 |
no fix listed |
Affected products
- n/a merge-deep2
Classification
- Weakness
-
- CWE-1321 Improperly Controlled Modification of Object Prototype Attributes
References
-
snyk.io
/vuln/SNYK-JS-MERGEDEEP2-1727593
web, exploit, mitigation, third-party-advisory
-
nvd.nist.gov
/vuln/detail/CVE-2021-23700
advisory
-
github.com
/luyuan/merge-deep
package
Sources
- CVE List CVE-2021-23700
- GitHub Advisory GHSA-j28q-p8ww-cp87
- NVD CVE-2021-23700
Fencer Vulns 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.