Description
An insecure default to allow UEFI Shell in EDK2 was left enabled in Ubuntu's EDK2. This allows an OS-resident attacker to bypass Secure Boot.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Canonical | Ubuntu EDK II | < 2023.05-2ubuntu0.1 | 2023.05-2ubuntu0.1 |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | edk2 | 2023.11-7 | — |
| Debian 13 | edk2 | 2023.11-7 | — |
| Debian 12 | edk2 | 2022.11-6+deb12u1 | DSA-5624-1 |
| Debian 11 | edk2 | 2020.11-2+deb11u2 | DSA-5624-1 |
| Debian 10 | edk2 | 0~20181115.85588389-3+deb10u4 | DLA-3852-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 22.04 LTS | edk2 | 2022.02-3ubuntu0.22.04.2 | USN-6638-1 |
| Ubuntu 20.04 LTS | edk2 | 0~20191122.bd85bf54-2ubuntu3.5 | USN-6638-1 |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 18.04 LTS | edk2 | No fix yet | — |
| Ubuntu Pro 16.04 LTS | edk2 | No fix yet | — |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | ovmf | 202308-7.1 | openSUSE-SU-2024:13807-1 |
Advisories 4
- USN-6638-1 edk2 vulnerabilities Ubuntu Security Notices (USN) · Apr 27, 2026
- DLA-3852-1 edk2 - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DSA-5624-1 edk2 - security update Debian Security (DSA / DLA) · Mar 9, 2026
- openSUSE-SU-2024:13807-1 ovmf-202308-7.1 on GA media SUSE / openSUSE Security Updates · May 7, 2025
References
- https://bugs.launchpad.net/ubuntu/+source/edk2/+bug/2040137 issue-tracking
- https://nvd.nist.gov/vuln/detail/CVE-2023-48733 issue-tracking
- https://www.openwall.com/lists/oss-security/2024/02/14/4 mailing-list
- https://bugs.launchpad.net/ubuntu/+source/lxd/+bug/2040139 issue-tracking
- https://lists.debian.org/debian-lts-announce/2024/06/msg00028.html