CVE-2020-21526

highpriority · track · 40EPSS 0.019 · 79 %ileEUUS

grimoire priorityP2 · Scheduled

Exploitable?

—

no known exploitation

Likely / severe?

1.89% (79th) EPSS

CVSS 7.5 · high

Is it mine?

2 products

Check your exposure

Who says so?

3 sources

cnnvd · enisa_euvd · nvd

EPSS · scored 2026-10-27

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

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

9.8

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · high–critical · 7.5–9.8

v2.07.5highAV:N/AC:L/Au:N/C:P/I:P/A:Pprimary · NVD / NIST USexploitability 10 · impact 6.4

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 5.9

v3.19criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-22USprimary

affected products (2)

Products and version ranges known to be affected.

n/a n/a≤ n/aenisa_euvdEU
halo halo= 1.1.3nvdUScpe:2.3:a:halo:halo:*:*:*:*:*:*:*:*

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd nvd NVD CVE.org MITRE

published 2020-09-30modified 2026-06-17

related (12,537)

Related entries.

ID	severity	EPSS	exploitable	published
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A directory traversal and file upload vulnerability allows an unauthenticated attacker to upload and execute arbitrary scripts on Check Point Management Server.
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GitLab has remediated an issue in GitLab CE/EE affecting all versions from 18.7 before 18.11.12, 19.0 before 19.0.9, 19.1 before 19.1.8, 19.2 before 19.2.6, and 19.3 before 19.3.2…
CVE-2026-66384US	—OT critical	0.66% (52nd)	KEV	2026-08-12
An authenticated user may write data outside the intended Docker cache path under specific remote-repository conditions.
CVE-2026-59310US	—OT critical	2.56% (85th)	KEV	2026-07-30
VMware vCenter contains a directory traversal vulnerability in the Syslog server. A malicious actor with network access to vCenter may exploit this issue to execute arbitrary code.

+12532 more

references (4)

External citations — patches, advisories, analysis.

https://github.com/halo-dev/halo/issues/421 cnnvd
https://nvd.nist.gov/vuln/detail/CVE-2020-21526 cnnvd
https://github.com/halo-dev/halo/issues/421 enisa_euvd
https://github.com/halo-dev/halo/issues/421ExploitIssue TrackingThird Party Advisorynvd

scry

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