diff --git a/FAQ.md b/FAQ.md index 4e9bb2ad..0848f56d 100644 --- a/FAQ.md +++ b/FAQ.md @@ -1930,6 +1930,31 @@ connection by the user and cryptsetup will stay true to that principle. + * **5.23 What is cryptsetup CVE-2021-4122?** + + CVE-2021-4122 describes a possible attack against data confidentiality + through LUKS2 online reencryption extension crash recovery. + + An attacker can modify on-disk metadata to simulate decryption in + progress with crashed (unfinished) reencryption step and persistently + decrypt part of the LUKS device. + + This attack requires repeated physical access to the LUKS device but + no knowledge of user passphrases. + + The decryption step is performed after a valid user activates + the device with a correct passphrase and modified metadata. + There are no visible warnings for the user that such recovery happened + (except using the luksDump command). The attack can also be reversed + afterward (simulating crashed encryption from a plaintext) with + possible modification of revealed plaintext. + + The problem was fixed in cryptsetup version 2.4.3 and 2.3.7. + + For more info, please see the report here: + https://seclists.org/oss-sec/2022/q1/34 + + # 6. Backup and Data Recovery