| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| 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. |
| UltraVNC through 1.8.2.2 uses inadequate cryptography in the MS-Logon II authentication scheme (rfbUltraVNC_MsLogonIIAuth). In rfb/dh.cpp the Diffie-Hellman key exchange is performed with parameters that fit in an unsigned 64-bit integer (DH_MAX_BITS controls the prime size). A 64-bit DH key can be broken by Pollard's rho algorithm in under one second on current hardware. Additionally, the private exponent is generated by the rng() function, which multiplies three libc rand() values seeded from time(NULL). With approximately 31 bits of internal state and a time-based seed, the private exponent is recoverable in under a minute by a passive observer. A network attacker who can observe the MS-Logon II handshake (via sniffing, recording, or man-in-the-middle) can derive the shared DH key and decrypt the encapsulated username and password, resulting in full credential disclosure. This affects legacy MS-Logon II connections; MS-Logon III (X25519 + AES-256-GCM) is unaffected. |
| The DoLogin Security plugin for WordPress is vulnerable to Authentication Bypass via Insufficient Randomness in all versions up to, and including, 4.3. The vulnerability exists because `dologin\s::rrand()` seeds the Mersenne Twister with `mt_srand((double) microtime() * 1000000)` — discarding the integer-seconds component of `microtime()` and constraining the seed to a range of approximately 10^6 values (~20 bits of entropy) — after which every character of the 32-character magic-link token is drawn sequentially with `mt_rand()`, making the entire token a deterministic function of that seed. Because `Pswdless::try_login()` is registered on the unauthenticated `init` hook, resolves the target account by the auto-increment numeric ID embedded in the `?dologin=<id>.<hash>` parameter, performs the hash comparison using a non-constant-time `!=` operator, and then calls `wp_set_auth_cookie()` directly — never passing through `wp_authenticate()` and therefore never triggering the plugin's own `Auth::_has_login_err()` lockout — an unauthenticated attacker can brute-force the ~10^6-candidate seed space to reconstruct an active passwordless login token and authenticate as any targeted user, including administrators, without a password. Exploitation requires that a valid, unexpired passwordless login link (active for up to 7 days) exists for the target account at the time of the attack, and that the numeric link ID is known or guessable from the auto-increment primary key. |
| 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. |
| Crypt::DSA versions before 1.22 for Perl draw the DSA signing nonce and private key from a biased random generator, leading to private-key recovery.
"Crypt::DSA::Util::makerandom forces the high bit of every value it returns to obtain an exactly N-bit integer for prime search. The signing nonce and the private key are drawn from makerandom. Because the high bit is always set, the result is not uniform: its top bit is fixed, producing insecure values."
An attacker who collects a modest number of signatures under an affected key, together with the public key, can recover the private key with a lattice attack.
Keys used to sign with an affected version should be considered compromised and new keys should be generated. |
| A flaw has been found in zcaceres markdownify-mcp up to 1.1.0. This impacts the function saveToTempFile of the file src/Markdownify.ts of the component webpage-to-markdown/youtube-to-markdown/bing-search-to-markdown. This manipulation causes insufficiently random values. The attack is restricted to local execution. A high degree of complexity is needed for the attack. The exploitability is said to be difficult. The exploit has been published and may be used. The pull request to fix this issue awaits acceptance. |
| Bytes::Random::Secure::Tiny versions through 1.011 for Perl share internal state across forked processes.
When an object is initialised before forking, then the internal state for the PRNG is shared across processes and identical random streams will be produced.
Secrets generated in multiprocess applications are predictable across processes. |
| Bytes::Random::Secure versions through 0.29 for Perl share internal state across forked processes.
When an object is initialised before forking, or when the functional interface is used, then the internal state for the PRNG is shared across processes and identical random streams will be produced.
Secrets generated in multiprocess applications are predictable across processes. |
| IBM Langflow OSS 1.0.0 through 1.10.0 Langflow could allow disclosure of all stored credentials due to the use of a weak and reversible key derivation mechanism for encryption at rest. |
| A flaw was found in the Avahi-daemon, where it initializes DNS transaction IDs randomly only once at startup, incrementing them sequentially after that. This predictable behavior facilitates DNS spoofing attacks, allowing attackers to guess transaction IDs. |
| A flaw was found in Avahi-daemon, which relies on fixed source ports for wide-area DNS queries. This issue simplifies attacks where malicious DNS responses are injected. |
| HTTP::Session versions before 0.54 for Perl defaults to using insecurely generated session ids.
HTTP::Session defaults to using HTTP::Session::ID::SHA1 to generate session ids using a SHA-1 hash seeded with the built-in rand function, the high resolution epoch time, and the PID. The PID will come from a small set of numbers, and the epoch time may be guessed, if it is not leaked from the HTTP Date header. The built-in rand function is unsuitable for cryptographic usage.
The distribution includes HTTP::session::ID::MD5 which contains a similar flaw, but uses the MD5 hash instead. |
| Incorrect use of the PUF key for user key generation in EFR32xG27 results in predictable keys |
| SYMCRYPTO is the SiXG301's host side hardware engine accessed by PSA crypto library that accelerates symmetric cryptographic operations (AES encryption/decryption and hashing).
DPA Countermeasures on SYMCRYPTO can be weakened (reduced entropy) by forcing certain seed values if an attacker gains code execution capability on the impacted device.
* Therefore, the keys loaded on SYMCRYPTO may be more vulnerable to extraction through DPA attacks than intended |
| Versions of the package jsrsasign from 7.0.0 and before 11.1.1 are vulnerable to Incomplete Comparison with Missing Factors via the getRandomBigIntegerZeroToMax and getRandomBigIntegerMinToMax functions in src/crypto-1.1.js; an attacker can recover the private key by exploiting the incorrect compareTo checks that accept out-of-range candidates and thus bias DSA nonces during signature generation. |
| The Pie Register WordPress plugin before 3.8.4.10 does not use sufficiently random values when generating its account verification tokens, allowing unauthenticated attackers to predict a valid token and activate an account without access to the associated email inbox. |
| In ManageEngine ADSelfService Plus, RecoveryManager Plus, M365 Manager Plus, and ADAudit Plus, the SSO tickets generated to authenticate that session could be predicted
by an unauthenticated user, leading to account takeover. |
| Dancer2::Plugin::Auth::OAuth versions before 0.22 for Perl default to a predictable nonce.
The default nonce was generated using an MD5 hash of the epoch time, which is predictable. |
| Mojolicious::Plugin::Web::Auth::OAuth2 versions through 0.17 for Perl have an insecure default state parameter.
When no state generator is specified in the constructor, the module defaults to using a SHA-1 hash of predictable and low-entropy sources, including the epoch time (which is leaked via the HTTP Date header) and a call to Perl's built-in rand function.
A predictable state allows an attacker to hijack another user's session through cross site request forgery (CSRF). |
| In JetBrains Hub before 2026.1.13757,
2025.3.148033,
2025.2.148048,
2025.1.148120,
2024.3.148430,
2024.2.148429 account takeover via predictable restore codes was possible |
