CVE-2026-52885— Notepad++ TOCTOU: HMAC Checks Disk, Executes from Memory

Notepad++ TOCTOU: HMAC Checks Disk, Executes from Memory

Notepad++ is a free and open-source source code editor. Prior to 8.9.6.4, NppCommands.cpp checks the HMAC of the on-disk shortcuts.xml at the moment a user command fires (Time-of-Check). However, the command payload is taken from the in-memory _userCommands vector, which is populated at application startup and never re-synchronized with the on-disk file (Time-of-Use). Swapping shortcuts.xml between startup and command execution causes the HMAC check to validate a clean file while a malicious command runs. An attacker with write access to shortcuts.xml places a malicious version on disk before launch, then immediately restores the legitimate file. The HMAC check at execution time validates the restored legitimate file (check passes), while the malicious payload executes from memory. This vulnerability is fixed in 8.9.6.4.

CVSS:4.0/AV:L/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

检查时间与使用时间(TOCTOU)的竞争条件

notepad-plus-plus 竞争条件问题漏洞

notepad-plus-plus notepad-plus-plus是notepad-plus-plus团队的一款文本编辑软件。 notepad-plus-plus 8.9.6.4之前版本存在竞争条件问题漏洞，该漏洞源于NppCommands.cpp中的检查时间与使用时间（TOCTOU）问题，可能导致具有shortcuts.xml写入权限的攻击者在启动前放置恶意版本并在加载后恢复合法文件，从而导致恶意载荷从内存中执行。

N/A

N/A