CVE-2026-7838
Description détaillée
UltraVNC viewer through 1.8.2.2 contains an integer overflow leading to a heap buffer overflow in the RFB protocol failure-response parsing path. In vncviewer/ClientConnection.cpp, the 4-byte network-supplied reasonLen field (type CARD32) is passed as reasonLen+1 to CheckBufferSize(). Because both operands are unsigned 32-bit, a reasonLen of 0xFFFFFFFF overflows to 0, causing CheckBufferSize to allocate only 256 bytes. The subsequent ReadString(m_netbuf, reasonLen) call then performs ReadExact for the original 4 GiB length into that 256-byte heap buffer. This overflow is reachable via rfbConnFailed (auth-scheme negotiation) and rfbVncAuthFailed (post-handshake) message types without successful authentication. A malicious VNC server, or any man-in-the-middle on the RFB stream, can trigger this condition when the victim viewer connects, potentially resulting in remote code execution as the user running the viewer. The crash was confirmed with AddressSanitizer on a portable reproduction harness (heap-buffer-overflow WRITE at offset 256).
Vecteur d'attaque (CVSS)
Références et Patchs
Dernières Vulnérabilités
CVE-2026-56016
CGI::Session::ID::md5 versions before 4.49 for Perl generate predictable session ids from low-entropy sources. The generate_id method builds the session id from a MD5 digest of the process id, the epoch time, and the built-in rand() function. All three are predictable, low-entropy sources: the PID is drawn from a small range, the epoch time can be guessed or read from the HTTP Date header, and Perl's rand() is unsuitable for security purposes because it is predictable and reversible. An attacker who predicts a session id can impersonate the corresponding session and bypass authentication.
CVE-2026-50043
Improper neutralization of special elements used in an OS command ('OS Command Injection') issue exists in SkyBridge MB-A100/MB-A110. If this vulnerability is exploited, an arbitrary OS command may be executed by an attacker who can log in to the product with an administrative privilege.
CVE-2026-13733
The Download Manager plugin for WordPress is vulnerable to Stored Cross-Site Scripting via 'no_data_msg' Shortcode Attribute in all versions up to, and including, 3.3.60 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. Although wp_kses_post is applied to post content on save, it only strips HTML tokens and does not neutralize C-style escape sequences embedded within shortcode attribute values, meaning contributors can craft a payload that survives the kses filter and is silently reconstructed into a raw script tag at render time.