CVE-2023-36811

Publication date 30 August 2023

Last updated 24 July 2024


Ubuntu priority

Cvss 3 Severity Score

4.7 · Medium

Score breakdown

borgbackup is an opensource, deduplicating archiver with compression and authenticated encryption. A flaw in the cryptographic authentication scheme in borgbackup allowed an attacker to fake archives and potentially indirectly cause backup data loss in the repository. The attack requires an attacker to be able to: 1. insert files (with no additional headers) into backups and 2. gain write access to the repository. This vulnerability does not disclose plaintext to the attacker, nor does it affect the authenticity of existing archives. Creating plausible fake archives may be feasible for empty or small archives, but is unlikely for large archives. The issue has been fixed in borgbackup 1.2.5. Users are advised to upgrade. Additionally to installing the fixed code, users must follow the upgrade procedure as documented in the change log. Data loss after being attacked can be avoided by reviewing the archives (timestamp and contents valid and as expected) after any "borg check --repair" and before "borg prune". There are no known workarounds for this vulnerability.

Status

Package Ubuntu Release Status
borgbackup 24.10 oracular
Not affected
24.04 LTS noble
Needs evaluation
23.10 mantic Ignored end of life, was needs-triage
23.04 lunar Ignored end of life, was needs-triage
22.04 LTS jammy
Needs evaluation
20.04 LTS focal
Needs evaluation
18.04 LTS bionic
Needs evaluation
16.04 LTS xenial
Needs evaluation
14.04 LTS trusty Ignored end of standard support

Severity score breakdown

Parameter Value
Base score 4.7 · Medium
Attack vector Local
Attack complexity High
Privileges required Low
User interaction None
Scope Unchanged
Confidentiality None
Integrity impact High
Availability impact None
Vector CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:N