description: During TLS 1.2 exchanges, handshake hashes are generated which point to a message buffer. This saved data is used for later messages but in some cases, the handshake transcript can exceed the space available in the current buffer, causing the allocation of a new buffer. This leaves a pointer pointing to the old, freed buffer, resulting in a use-after-free when handshake hashes are then calculated afterwards. This can result in a potentially exploitable crash. This vulnerability affects Firefox < 56, Firefox ESR < 52.4, and Thunderbird < 52.4.
problem types: Use-after-free in TLS 1.2 generating handshake hashes
affected:
{
product: Firefox
vendor: Mozilla
versions:
lessThan: 56, status: affected, version: unspecified, versionType: custom
}
{
product: Firefox ESR
vendor: Mozilla
versions:
lessThan: 52.4, status: affected, version: unspecified, versionType: custom
}
{
product: Thunderbird
vendor: Mozilla
versions:
lessThan: 52.4, status: affected, version: unspecified, versionType: custom
}
