CVE-2026-49953
Medium
Description
Discuz! X5.0 releases 20260320 through 20260610 contains a CAPTCHA bypass vulnerability that allows unauthenticated remote attackers to defeat challenge controls by exploiting limited complexity and predictable character sets in generated CAPTCHA images. Attackers can train a custom optical character recognition model against collected CAPTCHA samples to reliably predict challenge text, bypassing protections on login, registration, and other functionality from automated abuse.
SeverityMedium
CVSS6.5
Exploit probability—
ProductDiscuz! X5.0
PublishedJun 15, 2026
First seenJun 15, 2026
Weakness typeCWE-804CWE-804
How to fix
Sources list no fixed version or patch link for this vulnerability.
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| Discuz! Discuz! X5.0 | 20260320 ≤ v ≤ 20260610 | — |
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