Medium severity · published Feb 8, 2021
CVE-2021-26539
Apostrophe Technologies sanitize-html before 2.3.1 does not properly handle internationalized domain name (IDN) which could allow an attacker to bypass hostname whitelist…
5.3
CVSS
2%
EPSS
No
On KEV
Description
Apostrophe Technologies sanitize-html before 2.3.1 does not properly handle internationalized domain name (IDN) which could allow an attacker to bypass hostname whitelist validation set by the "allowedIframeHostnames" option.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)2.0% · higher than 80% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
SA
Sanitize-html · Apostrophecms
before 2.3.1 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-26539
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-26539
Exploit
https://advisory.checkmarx.net/advisory/CX-2021-4308
Release Notes
https://github.com/apostrophecms/sanitize-html/blob/main/CHANGELOG.md#231-2021-01-22
Patch
https://github.com/apostrophecms/sanitize-html/pull/458
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