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Vulnerability record · CVE-2020-21526 · published 30 September 2020

CVE-2020-21526: Halo path traversal vulnerability

Halo · Halo

An Arbitrary file writing vulnerability in halo v1.1.3. In an interface to write files in the background, a directory traversal check is performed on the input path parameter, but the startsWith function can be used to bypass it.

9.8 CVSS 3.1 Critical EPSS 1.9% · top 21.3% CWE-22 · Path traversal
9.8CVSS 3.1 base score, v2 7.5
1.9%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
2References, 2 tagged exploit
17 Jun 2026Last modified by NVD

Description

An Arbitrary file writing vulnerability in halo v1.1.3. In an interface to write files in the background, a directory traversal check is performed on the input path parameter, but the startsWith function can be used to bypass it.

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://github.com/halo-dev/halo/issues/421 ExploitIssue TrackingThird Party Advisory
https://github.com/halo-dev/halo/issues/421 ExploitIssue TrackingThird Party Advisory

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2020-21526), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.