Skip to content
Fencer Intel
medium 4.3

CVE-2021-36383 json

Xen Orchestra Mishandles Authorization

published 5y ago modified 4mo ago also GHSA-grvm-gcqf-gh8q , EUVD-2022-4005

cvss
4.3
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
0.7%
EPSS 0.7% chance of exploitation in 30 days, percentile 53%
public exploits
0
none known

Summary

Xen Orchestra (with xo-web through 5.80.0 and xo-server through 5.84.0) mishandles authorization, as demonstrated by modified WebSocket resourceSet.getAll data is which the attacker changes the permission field from none to admin. The attacker gains access to data sets such as VMs, Backups, Audit, Users, and Groups.

Is CVE-2021-36383 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.

Check with Fencer

Exploit prediction

0.71% chance of exploitation in the next 30 days, higher than 53% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • github.com https://github.com/vatesfr/xen-orchestra/issues/5712 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
NVD 3.1 4.3 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
NVD 2.0 4.0 AV:N/AC:L/Au:S/C:P/I:N/A:N
GitHub 3.1 4.3 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N

Affected packages

ecosystem package affected fixed in
npm xo-web
<=5.80.0
 no fix listed
npm xo-server
<=5.84.0
 no fix listed

Classification

Weakness

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.