CVE-2020-28499
Prototype Pollution
CVE-2020-28499 is a high vulnerability (CVSS 7.3) in Brikcss Merge, published February 18, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.44%, the 73rd percentile. Fixed in merge 2.1.1.
All versions of package merge are vulnerable to Prototype Pollution via _recursiveMerge .
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- Low
- Integrity
- Low
- Availability
- Low
Exploit likelihood
What each source reports
CVE List Score used
Prototype Pollution
All versions of package merge are vulnerable to Prototype Pollution via _recursiveMerge .
- Record
CVE-2020-28499- CVSS 3.1
- 7.3 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L/E:P - Updated
- 2026-11-02
EUVDEUVD-2021-1010
All versions of package merge are vulnerable to Prototype Pollution via _recursiveMerge .
- Record
EUVD-2021-1010- CVSS 3.1
- 7.3 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L/E:P - Updated
- 2026-11-03
GitHub AdvisoriesGHSA-7wpw-2hjm-89gp
Prototype Pollution in merge
All versions of package merge <2.1.1 are vulnerable to Prototype Pollution via _recursiveMerge .
- Record
GHSA-7wpw-2hjm-89gp- CVSS 3.1
- 7.3 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L - Weakness
- CWE-915
- Updated
- 2026-11-02
NVD
All versions of package merge are vulnerable to Prototype Pollution via _recursiveMerge .
- Record
CVE-2020-28499- CVSS 3.1
- 7.3 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L - CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - CVSS 2.0
- 7.5 High
AV:N/AC:L/Au:N/C:P/I:P/A:P - Updated
- 2026-11-02
OSV
All versions of package merge are vulnerable to Prototype Pollution via _recursiveMerge .
- Record
CVE-2020-28499- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVGHSA-7wpw-2hjm-89gp
Prototype Pollution in merge
All versions of package merge <2.1.1 are vulnerable to Prototype Pollution via _recursiveMerge .
- Record
GHSA-7wpw-2hjm-89gp- CVSS 3.1
- 7.3 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L - Weakness
- CWE-915
- Updated
- 2026-11-02
OSVROOT-APP-NPM-CVE-2020-28499 No score
CVE-2020-28499 in @rootio/merge - Patched by Root
Root has patched CVE-2020-28499 in the @rootio/merge package for Root:npm. Multiple fixed versions available.
- Record
ROOT-APP-NPM-CVE-2020-28499- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
mergenpm |
before 2.1.1 | 2.1.1 |
@rootio/mergeRoot:npm |
before 1.2.1-root.io.1 | 1.2.1-root.io.11.2.1-root.io.2 |
mergeRoot:npm |
before 1.2.1-aikido.2 | 1.2.1-aikido.2 |
History
| When | Changed | Sources |
|---|---|---|
| 2026-11-03 | aliases, products, published | EUVD |
| 2026-11-02 | created | CVE List, GitHub Advisories, NVD, OSV |
References
snyk.io/vuln/SNYK-JS-MERGE-1042987
github.com/yeikos/js.merge/blob/master/src/index.ts%23L64
nvd.nist.gov/vuln/detail/CVE-2020-28499
vuldb.com?id.170146