CVE-2026-53525 (GCVE-0-2026-53525)

Vulnerability from cvelistv5 – Published: 2026-08-21 22:19 – Updated: 2026-08-25 16:46
VLAI
Title
WeeChat has Non-Constant-Time Password Hash Comparison in Relay Authentication
Summary
WeeChat (Wee Enhanced Environment for Chat) is a free chat client. In versions 0.3.1 through 4.9.0, the WeeChat relay authentication uses non-constant-time string comparison functions (weechat_strcasecmp and strcmp) to verify password hashes and plaintext passwords. An attacker can exploit timing differences to extract the server-computed hash character by character, then authenticate using the correct hash without knowing the password. Version 4.9.1 fixes the issue.
Severity
7.4 (High)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:H
SSVC
Exploitation: poc Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-25 16:45 UTC
CWE
  • CWE-208 - Observable Timing Discrepancy
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7712 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
weechat weechat Affected: >= 0.3.4, < 4.9.1
guessed Create a notification for this product.
Show details on NVD website
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