Security readout for executives and security teams
Plain-English summary
deepmergefn can merge data in a way that may alter shared JavaScript object behavior. If an application uses it with untrusted input, attackers may affect logic, integrity, or availability in limited ways. Business urgency is moderate unless the package handles externally supplied data in critical services.
Executive priority
Treat as a moderate dependency risk. Escalate if deepmergefn is used in internet-facing services or security-sensitive configuration handling. Otherwise, remediate through normal dependency hygiene and confirm whether untrusted input reaches the vulnerable function.
Technical view
CVE-2021-23417 is prototype pollution in all reported versions of the npm package deepmergefn through its deepMerge function. The CVSS 3.1 score is 5.6 with network attack vector, high complexity, no privileges, no user interaction, and low confidentiality, integrity, and availability impact.
Likely exposure
Exposure is likely in JavaScript or Node.js applications that directly or transitively include deepmergefn and pass attacker-influenced objects into deepMerge. Installation alone does not prove exploitability; the vulnerable merge path must be reachable with untrusted data.
Exploitation context
The source bundle does not show CISA KEV listing or active exploitation. The CVSS vector records proof-of-concept exploit maturity, but no cited source in the bundle supports ongoing exploitation in the wild.
Researcher notes
The provided record lacks CWE mapping and does not name a patched version or vendor mitigation. Focus analysis on package reachability, input trust boundaries, and whether polluted prototype effects could influence authorization, validation, configuration, or availability in the application.
Mitigation direction
- Inventory direct and transitive use of deepmergefn in JavaScript projects.
- Check Snyk and upstream project guidance for fixed versions or recommended replacements.
- Prioritize services where deepMerge handles external request, API, or tenant-controlled data.
- If no fix exists, consider removing the dependency or isolating untrusted merge paths.
- Track remediation in dependency management tooling until the vulnerable package is absent.
Validation and detection
- Search dependency manifests and lockfiles for deepmergefn.
- Confirm whether deepMerge is reachable from externally supplied data.
- Review security scanners for CVE-2021-23417 or SNYK-JS-DEEPMERGEFN-1310984 findings.
- Verify deployed artifacts no longer contain the vulnerable dependency after remediation.
- Regression-test affected data merge workflows for expected behavior.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
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CVE-2021-23417 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Medium
- CVSS
- 5.6 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L/E:P/RL:U/RC:C
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L/E:P/RL:U/RC:C2.23.4Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
5.6MediumVector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L/E:P/RL:U/RC:C
Source materials
- CVE List V5 sourceCVE List V5
- https://snyk.io/vuln/SNYK-JS-DEEPMERGEFN-1310984CVE reference · x_refsource_MISC
- https://github.com/jesusgm/deepmergefn/blob/master/index.js%23L6CVE reference · x_refsource_MISC
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.