Medium severity · published Apr 30, 2026
CVE-2026-6539
Notepad++ 8.9.3 Format String Injection via nativeLang.xml
4.4
CVSS
0.2%
EPSS
No
On KEV
Description
Notepad++ 8.9.3 contains a format string injection vulnerability in the Find Results panel handler that allows attackers to cause denial of service and information disclosure by crafting a malicious nativeLang.xml language pack file. Attackers can distribute a poisoned language pack through community channels that triggers format string interpretation when a user performs search operations, leading to access violations and potential leakage of stack or register contents.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:L
Attack vector
Local
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
Low
Integrity
None
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 9% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
NO
Notepad++ · Notepad++
before 8.9.4 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-6539
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-6539
Release Notes
https://notepad-plus-plus.org/news/v894-released/
Third Party Advisory
https://www.vulncheck.com/advisories/notepad-format-string-injection-via-nativelang-xml
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