Foxit PDF Reader and Notepad++ flaws expose users to code execution and memory leaks
Foxit PDF Reader received fixes for two vulnerabilities in AcroForm Signature object handling that can be triggered when a user opens a malicious document or visits a malicious page. CVE-2026-5941 (ZDI-26-302) is a use-after-free flaw that can lead to remote code execution in the current process context, while CVE-2026-5942 (ZDI-26-303) is a related use-after-free bug that can disclose sensitive information and could be chained with other issues to achieve code execution. Zero Day Initiative said Foxit has released updates for the affected software.
Notepad++ also patched multiple vulnerabilities, including CVE-2026-3008, a string injection issue in the FindInFiles functionality tied to the nativeLang.xml find-result-hits field when it contains a %s format specifier. The flaw can crash the application or leak sensitive memory address information, and vendor reporting said CVE-2026-6539 was fixed in the same release. Notepad++ version 8.9.4 was issued to remediate the bugs, and Germany's dCERT separately warned that the product's vulnerabilities could enable denial of service or information disclosure.
Timeline
Apr 27, 2026
dCERT issues advisory on multiple Notepad++ vulnerabilities
Germany's dCERT published Advisory 2026-1260 warning that multiple Notepad++ vulnerabilities could allow denial of service or information disclosure. The advisory aligns with reporting around the patched Notepad++ flaws.
Apr 27, 2026
Notepad++ 8.9.4 released to fix CVE-2026-3008 and CVE-2026-6539
Notepad++ Product Owner Mr Hazley Samsudin released version 8.9.4 to remediate CVE-2026-3008, a string injection flaw in FindInFiles that can crash the application or leak memory address information, along with CVE-2026-6539. Patch details were published on the project's GitHub issue tracker.
Apr 27, 2026
ZDI publishes advisories for Foxit PDF Reader CVE-2026-5941 and CVE-2026-5942
The Zero Day Initiative publicly released advisories ZDI-26-302 and ZDI-26-303 covering Foxit PDF Reader vulnerabilities CVE-2026-5941 and CVE-2026-5942. ZDI said the bugs could enable remote code execution or information disclosure and noted the information disclosure issue could be chained with other flaws.
Mar 30, 2026
Foxit releases fixes for two PDF Reader AcroForm Signature flaws
Foxit made updates available to address two vulnerabilities in Foxit PDF Reader's handling of AcroForm Signature objects: CVE-2026-5941, a use-after-free remote code execution flaw, and CVE-2026-5942, a use-after-free information disclosure flaw. Both issues require user interaction such as opening a malicious file or visiting a malicious page.
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