HTTP::Tiny versions before 0.093 for Perl do not validate CRLF in HTTP request lines or control field header values. The unvalidated inputs are the method and URI in the request line, the URL host that becomes the `Host:` header, and HTTP/1.1 control data field values. An attacker who controls one of these inputs, for example a user supplied URL passed to a webhook or URL fetch endpoint, can inject additional headers and smuggle requests to the upstream server.

WebDyne::Session versions through 2.075 for Perl generates the session id insecurely. The session handler generates the session id from an MD5 hash seeded with a call to the built-in rand() function. The rand function is passed a maximum value based on the process id, the epoch time and the reference address of the object, but this information will have no effect on the overall quality of the seed of the message digest. The rand function is seeded by 32-bits and is predictable. It is considered unsuitable for cryptographic purposes. Predictable session ids could allow an attacker to gain access to systems. Note that WebDyne::Session versions 1.042 and earlier appear to be in separate distributions from WebDyne.

Net::Xero 0.044 and earlier for Perl uses the rand() function as the default source of entropy, which is not cryptographically secure, for cryptographic functions. Specifically Net::Xero uses the Data::Random library which specifically states that it is "Useful mostly for test programs". Data::Random uses the rand() function.

Apache::Session::Generate::SHA256 versions before 1.3.19 for Perl create insecure session ids. Apache::Session::Generate::SHA256 generated session ids insecurely. The default session id generator returns a SHA-256 hash of the built-in rand() function, the epoch time, and the PID, that is hashed again. These are predictable, low-entropy sources. Predicable session ids could allow an attacker to gain access to systems. Note that version 1.3.19 has a fallback without warning to use insecure session generation method if the call to Crypt::URandom::urandom fails. However, this is unlikely as Crypt::URandom is a hardcoded requirement of the module. This issue is similar to CVE-2025-40931 for Apache::Session::Generate::MD5.

Authen::DigestMD5 versions 0.01 through 0.02 for Perl generate the cnonce insecurely. The cnonce (client nonce) is generated from an MD5 hash of the PID, the epoch time and the built-in rand function. 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. According to RFC 2831, "The cnonce-value is an opaque quoted string value provided by the client and used by both client and server to avoid chosen plaintext attacks, and to provide mutual authentication. The security of the implementation depends on a good choice. It is RECOMMENDED that it contain at least 64 bits of entropy."

Authen::SASL::Perl::DIGEST_MD5 versions 2.04 through 2.1800 for Perl generates the cnonce insecurely. The cnonce (client nonce) is generated from an MD5 hash of the PID, the epoch time and the built-in rand function. 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. According to RFC 2831, The cnonce-value is an opaque quoted string value provided by the client and used by both client and server to avoid chosen plaintext attacks, and to provide mutual authentication. The security of the implementation depends on a good choice. It is RECOMMENDED that it contain at least 64 bits of entropy.