CVE-2026-44040
Description détaillée
UltraVNC through 1.8.2.2 uses a cryptographically weak pseudo-random number generator to produce VNC authentication challenge bytes. In rfb/vncauth.c:119-129, the vncRandomBytes() function seeds libc rand() with time(0) + getpid() + rand() and generates a 16-byte challenge. The combined seed space is approximately 31 bits (libc rand() internal state) and is entirely determined by publicly-observable values (wall-clock time and process ID). An attacker who can observe the authentication exchange can enumerate the seed space and predict the challenge within seconds, enabling forgery or offline brute-forcing of responses. Note: on Windows, the active code path may use vncEncryptBytes2.cpp which calls CryptGenRandom; reachability on shipped Windows binaries requires compile-graph verification and is under investigation.
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
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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.
