High-Severity Vulnerability in Notepad++

19 pointsposted 11 hours ago
by onlinenotepad
(csa.gov.sg)

9 Comments

gertlex

7 hours ago

Looks like it's a vulnerability in the installer.

From a small bit of skimming, sounds like it's a user escalation vector, where a low privileged user can run the installer in a contrived manner to achieve privilege escalation.

https://github.com/notepad-plus-plus/notepad-plus-plus/secur...

So for my personal install, nothing to worry about here...

user

an hour ago

[deleted]

reanimus

7 hours ago

Headline is a little misleading imo -- the vulnerability isn't in Notepad++ itself as much as its installer. Current users, I imagine, don't have anything to worry about.

notepad0x90

6 hours ago

Unless the updater also runs the installer, then you just drop your malicious dll in the right place and wait for an update, or find a way to force-trigger an update.

Attackers can also use the notepad installer as a payload execution mechanism. To run your malware, just get older notepad++ installers and drop your dll after the installer is running to run it as SYSTEM.

notepad0x90

6 hours ago

I wanted to say the installer has no business running things as SYSTEM but I suppose there is no way around that for registering COM DLLs. I would think Attackers would need to chain this with a Uac bypass (or be fortunate enough to find Uac disabled). If Uac is setup right, administrative operations like regsvr32 should require going through consent.exe's prompt. Uac bypasses are plenty but systems can be configured to mitigate them (at least the ones I know of). Social engineering is also another good way to bypass Uac.

retox

7 hours ago

If the problem is in the installer then this can't be 'fixed', affected installers should be fingerprinted as malware.

gertlex

36 minutes ago

I had that thought of "existing installers are sus..." but didn't connect to "fingerprinting it as malware". Makes sense.

Couple questions as savvy tech person but not working day-to-day in security/IT:

Would a regular home user with an old installer in their Downloads folder need to worry? (is a bad download file going to target looking for these old installers, then moving files around, etc?)

On the other hand, I could see corporate IT having the stronger case of proactively wanting to flag this installer if present on their systems.