CVE-2017-14727

What it actually does

Uninitialized buffer in logger.c allows remote crash when processing crafted strftime date/time format specifiers in the logger plugin.

Why it matters to the business

WeeChat IRC clients experience denial-of-service crashes, interrupting chat sessions and logging for users on affected versions; the issue is long-public with no known active exploitation campaigns.

How an attack unfolds

An attacker connects to a WeeChat user running the logger plugin and supplies input containing malicious strftime specifiers that trigger use of the uninitialized buffer, causing an immediate crash.

How to fix it

Upgrade WeeChat to the fixed commit f105c6f0b56fb5687b2d2aedf37cb1d1b434d556 or release 1.9.1 or later; disable the logger plugin as a temporary workaround if upgrade is not immediately possible.

How to confirm the fix worked

Verify WeeChat version is 1.9.1 or newer or contains commit f105c6f0b56fb5687b2d2aedf37cb1d1b434d556; attempt to reproduce the crash with known triggering strftime specifiers in a test environment.

Typical attack path

1. Identify WeeChat users running vulnerable versions with logger plugin enabled
2. Send crafted messages or triggers containing strftime format specifiers via IRC or other chat protocols
3. Trigger logger code path that calls strftime on the malformed input
4. Cause uninitialized buffer access resulting in crash

How to detect it

Search application and system logs for abrupt WeeChat process terminations correlated with logger plugin activity or strftime-related calls; review chat logs for unusual date/time format strings around crash timestamps.

What your security team should do

• Prioritize upgrade of all WeeChat installations to the fixed version
• Review logging configurations and consider temporarily disabling the logger plugin on high-risk systems
• Monitor vendor advisories for any follow-on patches