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Fencer Intel
high 8.1

CVE-2021-29452 json

Any logged in user could edit any other logged in user.

published 5y ago modified 4mo ago also GHSA-8hw9-22v6-9jr9 , EUVD-2021-0800

cvss
8.1
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.8%
EPSS 0.8% chance of exploitation in 30 days, percentile 56%
public exploits
0
none known

Summary

a12n-server is an npm package which aims to provide a simple authentication system. A new HAL-Form was added to allow editing users in version 0.18.0. This feature should only have been accessible to admins. Unfortunately, privileges were incorrectly checked allowing any logged in user to make this change. Patched in v0.18.2.

Patch / fix

  • npm @curveball/a12n-server 0.18.2
  • curveballjs a12n-server 0.18.2

Is CVE-2021-29452 in your dependencies? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

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Exploit prediction

0.78% chance of exploitation in the next 30 days, higher than 56% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
CNA 3.1 8.1 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
NVD 3.1 6.5 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
NVD 2.0 4.0 AV:N/AC:L/Au:S/C:N/I:P/A:N
GitHub 3.1 8.1 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

Affected packages

ecosystem package affected fixed in
npm @curveball/a12n-server
>=0.18.0, <0.18.2
0.18.2

Affected products

  • curveball a12n-server

Classification

Weakness
  • CWE-269 Improper Privilege Management
  • CWE-863 Incorrect Authorization

References

Sources

Fencer Intel 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.