CVE-2021-43787

mediumpriority · track · 24EPSS 0.013 · 71 %ileEUUS
grimoire priorityP3 · Track
Exploitable?
—
no known exploitation
Likely / severe?
1.32% (71st) EPSS
CVSS 4.3 · medium
Is it mine?
3 products
Check your exposure
Who says so?
4 sources
cnnvd · enisa_euvd · nvd · osv

EPSS · scored 2026-10-27

Nodebb is an open source Node.js based forum software. In affected versions a prototype pollution vulnerability in the uploader module allowed a malicious user to inject arbitrary data (i.e. javascript) into the DOM, theoretically allowing for an account takeover when used in conjunction with a path traversal vulnerability disclosed at the same time as this report. The vulnerability has been patched as of v1.18.5. Users are advised to upgrade as soon as possible.

01

cvss

Technical severity, 0–10. One row per scoring source.

9.0
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–critical · 4.3–9

v2.04.3mediumAV:N/AC:M/Au:N/C:N/I:P/A:Nprimary · NVD / NIST USexploitability 8.6 · impact 2.9
v3.16.1mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:Nprimary · NVD / NIST USexploitability 2.8 · impact 2.7
v3.19criticalCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:Hsecondary · ENISA EU
v3.19criticalCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:Hsecondary · security-advisories@github.comexploitability 2.3 · impact 6
v3.19criticalCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:Hsecondary · OSV
v3.15.6mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N/E:Usecondary · CVSS-BT (t0sche)
02

weaknesses

The CWE weakness classes this flaw belongs to.

03

affected products (3)

Products and version ranges known to be affected.

04

advisories (1)

Vendor and ecosystem advisories describing this.

  • GHSA-wx69-rvg3-x7fcXSS via prototype pollution in NodeBB 2021-11-30ghsa · osvUS

    ### Impact A prototype pollution vulnerability in the uploader module allowed a malicious user to inject arbitrary data (i.e. javascript) into the DOM, theoretically allowing for an account takeover when used in conjunction with a path traversal vulnerability disclosed at the same time as this report. ### Patches The vulnerability has been patched as of v1.18.5. ### Workarounds Cherry-pick commit hash 1783f918bc19568f421473824461ff2ed7755e4c to receive this patch in lieu of a full upgrade. ### For more information If you have any questions or comments about this advisory: * Email us at [security@nodebb.org](mailto:security@nodebb.org)

05

also known as (3)

Other names and identifiers for this entity.

06

sources

Which sources assert this record, and when.

published 2021-11-29modified 2026-06-17
08

references (13)

External citations — patches, advisories, analysis.

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