Looks good to me on gpg4win-5.0.2-beta2 @ win11:

• first manual gpg -K and gpgsm -K displays the correct output now
• the loop ran without a hang for 50 times

I found that it's not that simple to accept the case of no newline at the end.
Because we need to handle the edge case where no newline occurs at the maximum buffer length, too.
It's something like the following.

I found two issues in libgpg-error for spawning functions.

Oh yeah, the mentioned patch is bogus because it assumes that fgets has already set the eof flag while reading the last line. This seems not to be the case.

I added the gpgsm log output in the description (same error as in the gpg log)

To reproduce the hang, a loop will suffice (usually happens within the first 15 times, once it needed 50 runs):

I have this fix committed to my working directory:

We have no CVE yet. However, CVE is also a good tag for security bugs,

On 2026-01-20, I found the message to security@gnupg.org of:
Message-ID: 4e708880-04ac-45bc-8d16-6b585f2652a1n@aisle.com
in may spam folder. It has a 10MB long attachment. That might be one of reasons to be identified as a spam.

This does not happen any more, tested with Gpg4win-5.0.0-beta479

fix tested and confirmed with GnuPG 2.5.12 on windows 10

i've included logfiles for gpg-agent and scdaemon with debug-level 10. the files include

We will do a new gpg4win beta soon.

@m.eik Could you please enable debug option for gpg-agent and get the log output for the crash?