Medium severity · published Jan 12, 2026
CVE-2025-66939
Cross Site Scripting vulnerability in 66biolinks by AltumCode v.61.0.1 allows an attacker to execute arbitrary code via a crafted favicon file
5.4
CVSS
0.3%
EPSS
No
On KEV
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 18% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
66
66biolinks · Altumcode
61.0.1 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-66939
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-66939
Product
https://66biolinks.com/
Exploit
https://gist.github.com/Waqar-Arain/2a21b135a04e7804c124688ea1085875
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