CVE-2021-26540

Published: Feb 8, 2021Updated: Nov 21, 2024 Sources: CVE List NVD GHSANVD-CWE-noinfo

5.3MEDIUM

NVD MITRE

Description

Apostrophe Technologies sanitize-html before 2.3.2 does not properly validate the hostnames set by the "allowedIframeHostnames" option when the "allowIframeRelativeUrls" is set to true, which allows attackers to bypass hostname whitelist for iframe element, related using an src value that starts with "/\\example.com".

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:NAttack Vector

Network

AC:LAttack Complexity

Low

PR:NPrivileges Required

None

UI:NUser Interaction

None

Scope

S:UScope

Unchanged

Impact

C:NConfidentiality

None

I:LIntegrity

Low

A:NAvailability

None

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Weaknesses

NVD-CWE-noinfo

Affected Products

apostrophecms

commercialaka apostrophe

sanitize-htmlOn-prem

Web & CMS Plugins / cms-core

npm

package-ecosystem

sanitize-html

OSS Libraries

and 1 more affected products View all →

Exploitability

1 exploit source identified

Exploit details including PoC links, Metasploit modules, and scanner templates are available after registration.

View exploit details

Official Patch Available

Is your org exposed to CVE-2021-26540?Request an assessment to establish which checks are appropriate for your systems. Check my exposure

References

https://github.com/apostrophecms/sanitize-html/blob/main/CHANGELOG.md#232-2021-01-26

github.com

https://github.com/apostrophecms/sanitize-html/pull/460

github.com

https://advisory.checkmarx.net/advisory/CX-2021-4309

advisory.checkmarx.net

and 1 more references View all →

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