CVE-2023-51767
Publication date 24 December 2023
Last updated 24 July 2024
Ubuntu priority
OpenSSH through 9.6, when common types of DRAM are used, might allow row hammer attacks (for authentication bypass) because the integer value of authenticated in mm_answer_authpassword does not resist flips of a single bit. NOTE: this is applicable to a certain threat model of attacker-victim co-location in which the attacker has user privileges.
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| openssh | ||
| 22.04 LTS jammy | Ignored | |
| 20.04 LTS focal | Ignored | |
| 18.04 LTS bionic | Ignored | |
| 16.04 LTS xenial | Ignored | |
| 14.04 LTS trusty | Ignored | |
| openssh-ssh1 | ||
| 22.04 LTS jammy | Ignored | |
| 20.04 LTS focal | Ignored | |
| 18.04 LTS bionic | Ignored | |
| 16.04 LTS xenial | Not in release | |
| 14.04 LTS trusty | Not in release |
Notes
seth-arnold
openssh-ssh1 is provided for compatibility with old devices that cannot be upgraded to modern protocols. Thus we may not provide security support for this package if doing so would prevent access to equipment.
mdeslaur
The researchers used a modified version of sshd to make this vulnerability easier to demonstrate. There is no indication the openssh package in Ubuntu can be exploited in the same way. The upstream OpenSSH developers have chosen to ignore this issue as this vulnerability isn't exploitable in practice, and needs to be addressed by the hardware platform, not in OpenSSH itself. Since there is nothing actionable here for Ubuntu, I am marking this issue as ignored.
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score |
7.0 · High
|
| Attack vector | Local |
| Attack complexity | High |
| Privileges required | Low |
| User interaction | None |
| Scope | Unchanged |
| Confidentiality | High |
| Integrity impact | High |
| Availability impact | High |
| Vector | CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H |