Threat Intelligence Database

Snap7 through 1.4.3 contains an out-of-bounds write vulnerability in the passive partner that allows a malicious active partner to overflow application buffers by declaring an unvalidated BSend total length. Attackers connecting from the configured peer address can declare up to 65535 bytes and send a short fragment, causing BRecv to memcpy past the buffer and crash or corrupt SCADA, HMI or gateway processes.

snap7 versions up to and including 1.4.3 have an out-of-bounds write vulnerability in the TSnap7MicroClient::opReadArea() function. This flaw allows malicious or impersonated S7 peers to overflow client buffers by exploiting an unchecked DataLength field. Crafted ReadVar responses can cause memcpy operations of up to 65535 bytes into caller buffers, potentially crashing SCADA, HMI, or gateway processes and corrupting memory.

A vulnerability was determined in davenardella snap7 up to 1.4.3. The affected element is the function TSnap7MicroClient::opUpload of the file src/core/s7_micro_client.cpp. Executing a manipulation of the argument DataLen can lead to memory corruption. The attack can be executed remotely. The exploit has been publicly disclosed and may be utilized. The project was informed of the problem early through an issue report but has not responded yet.

A security flaw has been discovered in davenardella snap7 up to 1.4.3. The impacted element is the function TSnap7Peer::NegotiatePDULength of the file src/core/s7_peer.cpp. The manipulation of the argument PDULength results in out-of-bounds write. The attack can be executed remotely. The exploit has been released to the public and may be used for attacks.

A flaw has been found in davenardella snap7 up to 1.4.3. This affects the function TS7Worker::PerformFunctionRead of the file src/core/s7_server.cpp of the component ReadVar Request Handler. This manipulation causes out-of-bounds write. The attack requires access to the local network. The exploit has been published and may be used. The project was informed of the problem early through an issue report but has not responded yet.