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Fencer Intel
critical 9.8

CVE-2020-21522 json

An issue was discovered in halo V1.1.3.

published 6y ago modified 4mo ago also EUVD-2020-14290

cvss
9.8
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
1.5%
EPSS 1.5% chance of exploitation in 30 days, percentile 74%
public exploits
0
none known

Summary

An issue was discovered in halo V1.1.3. A Zip Slip Directory Traversal Vulnerability in the backend,the attacker can overwrite some files, such as ftl files, .bashrc files in the user directory, and finally get the permissions of the operating system.

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Exploit prediction

1.53% chance of exploitation in the next 30 days, higher than 74% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • github.com https://github.com/halo-dev/halo/issues/418 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
NVD 3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD 2.0 7.5 AV:N/AC:L/Au:N/C:P/I:P/A:P

Classification

Weakness
  • CWE-22 Improper Limitation of a Pathname to a Restricted Directory

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.