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CVE-2021-26540

Published: Feb 8, 2021Updated: Nov 21, 2024 Sources: CVE List NVD GHSANVD-CWE-noinfo
NVD MITRE
5.3CVSSMEDIUM
EPSS Score
1.8%
Top 25.0%
CISA KEV
Not in KEV
Exploits
1 Known
Remediation
Patch Available

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".

CVSS Vector Breakdown

AV:NAC:LPR:NUI:NS:UC:NI:LA:N
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

n/an/a
sanitize-htmlapostrophecms
On-prem
Web & CMS Plugins / cms-core
sanitize-htmlnpmOSS Libraries
apostrophecmscommercialWeb & CMS Pluginsaka apostrophecms, apostrophe
npmpackage-ecosystemOSS Libraries

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

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 →

Timeline

Published
Feb 8, 2021
Last Updated
Nov 21, 2024

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