Cyber Resilience

CVE-2021-35976

MediumPublic PoC

Published: 10 September 2021

Published
10 September 2021
Modified
21 November 2024
KEV Added
Patch
CVSS Score v3.1 6.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
EPSS Score 0.0053 67.7th percentile
Risk Priority 13 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-35976 is a medium-severity Cross-site Scripting (CWE-79) vulnerability in Plesk Obsidian. Its CVSS base score is 6.1 (Medium).

Operationally, ranked in the top 32.3% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

EU & UK References

Vulnerability details

The feature to preview a website in Plesk Obsidian 18.0.0 through 18.0.32 on Linux is vulnerable to reflected XSS via the /plesk-site-preview/ PATH, aka PFSI-62467. The attacker could execute JavaScript code in the victim's browser by using the link to…

more

preview sites hosted on the server. Authentication is not required to exploit the vulnerability.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

plesk
obsidian
18.0.0 — 18.0.32

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-79

Penetration testing submits XSS payloads to web applications, detecting cross-site scripting flaws for subsequent remediation.

addresses: CWE-79

Validates web inputs to reject script-related content that could produce XSS.

addresses: CWE-79

Output validation against expected content can reject or sanitize script content in generated web pages, reducing XSS exploitability.

References