CVE-2024-56738 Information disclosure in GRUB2
Medium 5.3
Published
Updated
Check this codebase for CVE-2024-56738 and fix it if it is affected.
What it is: CVE-2024-56738 is a medium-severity vulnerability in GNU GRUB2, published on 29 Dec 2024. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2024-56738 in the wild and no public exploit code.
Affected product: GNU GRUB2. No package-level version data is available, so check the vendor advisory linked from the reference page.
Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.
Reference: https://insights.sbomify.com/CVE-2024-56738/ (Markdown: https://insights.sbomify.com/CVE-2024-56738/index.md)
Attackers can exploit timing side-channels in GRUB's cryptographic comparison to potentially recover sensitive data.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2024-56738?
CVE-2024-56738 is a medium-severity vulnerability in GNU GRUB2, published on 29 Dec 2024. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
GNU GRUB (aka GRUB2) through 2.12 does not use a constant-time algorithm for grub_crypto_memcmp and thus allows side-channel attacks.
Which versions are affected by CVE-2024-56738?
It affects 1 product.
Linux distribution packages (13)
grub2 SUSE:Linux Enterprise Micro 5.1 | All versions | 2.04-150300.3.14.2 |
grub2 SUSE:Linux Enterprise Micro 5.2 | All versions | 2.04-150300.22.58.1 |
grub2 SUSE:Linux Enterprise Micro 5.3 | All versions | 2.06-150400.11.63.1 |
grub2 SUSE:Linux Enterprise Micro 5.4 | All versions | 2.06-150400.11.63.1 |
grub2 SUSE:Linux Enterprise Micro 5.5 | All versions | 2.06-150500.29.53.1 |
grub2 SUSE:Linux Enterprise Module for Basesystem 15 SP6 | All versions | 2.12-150600.8.34.1 |
grub2 SUSE:Linux Enterprise Module for Basesystem 15 SP7 | All versions | 2.12-150700.19.13.2 |
grub2 SUSE:Linux Enterprise Module for Server Applications 15 SP6 | All versions | 2.12-150600.8.34.1 |
grub2 SUSE:Linux Enterprise Module for Server Applications 15 SP7 | All versions | 2.12-150700.19.13.2 |
grub2 SUSE:Linux Enterprise Server LTSS Extended Security 12 SP5 | All versions | 2.02-190.1 |
grub2 SUSE:Linux Micro 6.0 | All versions | 2.12~rc1-7.1 |
grub2 openSUSE:Leap 15.6 | All versions | 2.12-150600.8.34.1 |
grub2 openSUSE:Tumbleweed | All versions | 2.12-56.1 |
Products include Gnu Grub2.
How do I fix CVE-2024-56738?
Apply the vendor's patch.
Is CVE-2024-56738 being exploited?
There is no known exploitation of CVE-2024-56738 in the wild and no public exploit code.
Other vulnerabilities in GNU GRUB2
- CVE-2024-56737 Memory corruption in GRUB2
- CVE-2022-28733 Integer underflow in grub_net_recv_ip4_packets
- CVE-2022-28734 Out-of-bounds write when handling split HTTP headers
- CVE-2025-61662 Grub2: missing unregister call for gettext command may lead to use-after-free
- CVE-2024-45782 Grub2: fs/hfs: strcpy() using the volume name (fs/hfs.c:382)
Sources
Also known as AZL-54692, AZL-54709, BELL-CVE-2024-56738, CLSA-2026-1788432569, DEBIAN-CVE-2024-56738, GHSA-9gmj-v2m8-qffv and 11 more.