The client side in OpenSSH 5.7 through 8.4 has an Observable Discrepancy leading to an information leak in the algorithm negotiation. This allows man-in-the-middle attackers to target initial connection attempts (where no host key for the server has been cached by the client). NOTE: some reports state that 8.5 and 8.6 are also affected.
The product behaves differently or sends different responses under different circumstances in a way that is observable to an unauthorized actor, which exposes security-relevant information about the state of the product, such as whether a particular operation was successful or not.
Name | Vendor | Start Version | End Version |
---|---|---|---|
Openssh | Openbsd | 5.7 (including) | 8.4 (excluding) |
Openssh | Openbsd | 8.4 (including) | 8.4 (including) |
Openssh | Openbsd | 8.5 (including) | 8.5 (including) |
Openssh | Openbsd | 8.6 (including) | 8.6 (including) |
Red Hat Enterprise Linux 8 | RedHat | openssh-0:8.0p1-10.el8 | * |
Red Hat Enterprise Linux 8 | RedHat | openssh-0:8.0p1-10.el8 | * |
Openssh | Ubuntu | bionic | * |
Openssh | Ubuntu | eoan | * |
Openssh | Ubuntu | focal | * |
Openssh | Ubuntu | groovy | * |
Openssh | Ubuntu | hirsute | * |
Openssh | Ubuntu | impish | * |
Openssh | Ubuntu | kinetic | * |
Openssh | Ubuntu | lunar | * |
Openssh | Ubuntu | mantic | * |
Openssh | Ubuntu | precise/esm | * |
Openssh | Ubuntu | trusty | * |
Openssh | Ubuntu | trusty/esm | * |
Openssh | Ubuntu | upstream | * |
Openssh | Ubuntu | xenial | * |
Openssh-ssh1 | Ubuntu | bionic | * |
Openssh-ssh1 | Ubuntu | eoan | * |
Openssh-ssh1 | Ubuntu | focal | * |
Openssh-ssh1 | Ubuntu | groovy | * |
Openssh-ssh1 | Ubuntu | hirsute | * |
Openssh-ssh1 | Ubuntu | impish | * |
Openssh-ssh1 | Ubuntu | kinetic | * |
Openssh-ssh1 | Ubuntu | lunar | * |
Openssh-ssh1 | Ubuntu | mantic | * |
Openssh-ssh1 | Ubuntu | upstream | * |