CVE-2021-3418
published 2021-03-15CVE-2021-3418: If certificates that signed grub are installed into db, grub can be booted directly. It will then boot any kernel without signature validation. The booted…
PriorityP427medium6.4CVSS 3.1
AVLACHPRHUINSUCHIHAH
EPSS
0.47%
37.8th percentile
If certificates that signed grub are installed into db, grub can be booted directly. It will then boot any kernel without signature validation. The booted kernel will think it was booted in secureboot mode and will implement lockdown, yet it could have been tampered. This flaw is a reintroduction of CVE-2020-15705 and only affects grub2 versions prior to 2.06 and upstream and distributions using the shim_lock mechanism.
Affected
3 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | grub2 | — | — |
| gnu | grub2 | < 2.06 | 2.06 |
| msrc | cbl2_grub2_2.06rc1-7_on_cbl_mariner_2.0 | — | — |
CVSS provenance
nvdv3.16.4MEDIUMCVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H
nvdv2.04.4MEDIUMAV:L/AC:M/Au:N/C:P/I:P/A:P
osv6.4MEDIUM
vendor_debian6.4LOW
vendor_msrc6.4MEDIUM
vendor_redhat6.4MEDIUM
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Microsoft
If certificates that signed grub are installed into db grub can be booted directly. It will then boot any kernel without signature validation. The booted kernel will think it was booted in secureboot
vendor_msrc·2021-03-09·CVSS 6.4
CVE-2021-3418 [MEDIUM] CWE-281 If certificates that signed grub are installed into db grub can be booted directly. It will then boot any kernel without signature validation. The booted kernel will think it was booted in secureboot
If certificates that signed grub are installed into db grub can be booted directly. It will then boot any kernel without signature validation. The booted kernel will think it was booted in secureboot mode and will implement lockdown yet it could have been tampered. This flaw is a reintroduction of CVE-2020-15705 and only affects grub2 versions prior to 2.06 and upstream and distributions using the shim_lock mechanism.
FAQ: Is Azure Linux the only Microsoft product that includes this open-source library and is therefore potentially affected by this vulnerability?
One of the main benefits to our customers who choose to use the Azure Linux distro is the commitment to keep it up to date with the most recent and most secure versions of the open source libraries with which the distro is compose
Red Hat
grub2: grub 2.05 reintroduced CVE-2020-15705
vendor_redhat·2021-03-02·CVSS 6.4
CVE-2021-3418 [MEDIUM] CWE-281 grub2: grub 2.05 reintroduced CVE-2020-15705
grub2: grub 2.05 reintroduced CVE-2020-15705
If certificates that signed grub are installed into db, grub can be booted directly. It will then boot any kernel without signature validation. The booted kernel will think it was booted in secureboot mode and will implement lockdown, yet it could have been tampered. This flaw is a reintroduction of CVE-2020-15705 and only affects grub2 versions prior to 2.06 and upstream and distributions using the shim_lock mechanism.
A flaw was found in grub. If certificates that signed grub are installed into db, grub can be booted directly. It will then boot any kernel without signature validation. The booted kernel will think it was booted in secureboot mode and will implement lockdown, yet it could have been tampered. This flaw is a reintroduction of CV
Debian
CVE-2021-3418: grub2 - If certificates that signed grub are installed into db, grub can be booted direc...
vendor_debian·2021·CVSS 6.4
CVE-2021-3418 [MEDIUM] CVE-2021-3418: grub2 - If certificates that signed grub are installed into db, grub can be booted direc...
If certificates that signed grub are installed into db, grub can be booted directly. It will then boot any kernel without signature validation. The booted kernel will think it was booted in secureboot mode and will implement lockdown, yet it could have been tampered. This flaw is a reintroduction of CVE-2020-15705 and only affects grub2 versions prior to 2.06 and upstream and distributions using the shim_lock mechanism.
Scope: local
bookworm: resolved
bullseye: resolved
forky: resolved
sid: resolved
trixie: resolved
GHSA
GHSA-j6wm-c7q8-jcx7: If certificates that signed grub are installed into db, grub can be booted directly
ghsa_unreviewed·2022-05-24·CVSS 6.4
CVE-2021-3418 [MEDIUM] CWE-281 GHSA-j6wm-c7q8-jcx7: If certificates that signed grub are installed into db, grub can be booted directly
If certificates that signed grub are installed into db, grub can be booted directly. It will then boot any kernel without signature validation. The booted kernel will think it was booted in secureboot mode and will implement lockdown, yet it could have been tampered. This flaw is a reintroduction of CVE-2020-15705 and only affects grbu2 versions prior to 2.06 and upstream and distributions using the shim_lock mechanism.
OSV
CVE-2021-3418: If certificates that signed grub are installed into db, grub can be booted directly
osv·2021-03-15·CVSS 6.4
CVE-2021-3418 [MEDIUM] CVE-2021-3418: If certificates that signed grub are installed into db, grub can be booted directly
If certificates that signed grub are installed into db, grub can be booted directly. It will then boot any kernel without signature validation. The booted kernel will think it was booted in secureboot mode and will implement lockdown, yet it could have been tampered. This flaw is a reintroduction of CVE-2020-15705 and only affects grub2 versions prior to 2.06 and upstream and distributions using the shim_lock mechanism.
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2021-03-15
Published