CVE-2021-4264 | LinkedIn dustjs prototype pollution

Exp

A vulnerability was found in LinkedIn dustjs up to 2.x and classified as problematic. Affected by this issue is some unknown functionality. The manipulation leads to improperly controlled modification of object prototype attributes ('prototype pollution'). The attack may be launched remotely. The exploit has been disclosed to the public and may be used. Upgrading to version 3.0.0 is able to address this issue. The name of the patch is ddb6523832465d38c9d80189e9de60519ac307c3. It is recommended to upgrade the affected component. The identifier of this vulnerability is VDB-216464.

Published: 2022-12-21 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2021-4264 is rated High Exploit Risk (61.7/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 1.07%). Core evidence: 2 public exploit reference(s) are indexed (Exploit-DB). Mandatory action: Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2021-4264

EDB-ID Source Kind Published Link
nvd_ref exploit_tag Exploit-DB ↗
nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2021-4264

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.70% 1.07% +0.37%
2 2026-04-01 0.89% 0.70% -0.20%
3 2026-03-21 0.89%

Full EPSS history (20 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-4264

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.3 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:L)
Might cause slowdowns, glitches, or partial disruption—not a full brick.
2.8 3.4 [email protected]
8.8 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
2.8 5.9 [email protected]

Weakness enumeration for CVE-2021-4264

GitHub Security Advisory for CVE-2021-4264

GHSA-c6rp-wrp9-qr4q · Severity: high · Ecosystem: npm — dustjs-linkedin vulnerable to Prototype Pollution

Affected software / configurations for CVE-2021-4264

Vendor Product Version Raw CPE
linkedin dustjs < 3.0.0 cpe:2.3:a:linkedin:dustjs:*:*:*:*:*:*:*:*

References for CVE-2021-4264

URL Tags
https://github.com/linkedin/dustjs/commit/ddb6523832465d38c9d80189e9de60519ac307c3 Patch Third Party Advisory
https://github.com/linkedin/dustjs/issues/804 Exploit Issue Tracking Third Party Advisory
https://github.com/linkedin/dustjs/pull/805 Exploit Issue Tracking Patch Third Party Advisory
https://github.com/linkedin/dustjs/releases/tag/v3.0.0 Release Notes Third Party Advisory
https://vuldb.com/?ctiid.216464 VDB Entry
https://vuldb.com/?id.216464 Third Party Advisory VDB Entry
cvelogic Threat Intelligence