CVE-2026-43289 kexec: derive purgatory entry from symbol
A flaw in the Linux kernel kexec subsystem can trigger a kernel warning and potential crash when loading purgatory images with overlapping executable sections.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-43289?
CVE-2026-43289 is a medium-severity denial of service vulnerability in Linux kernel, published on 8 May 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
kexec: derive purgatory entry from symbol
kexec_load_purgatory() derives image->start by locating e_entry inside an SHF_EXECINSTR section. If the purgatory object contains multiple executable sections with overlapping sh_addr, the entrypoint check can match more than once and trigger a WARN.
Derive the entry section from the purgatory_start symbol when present and compute image->start from its final placement. Keep the existing e_entry fallback for purgatories that do not expose the symbol.
WARNING: kernel/kexec_file.c:1009 at kexec_load_purgatory+0x395/0x3c0, CPU#10: kexec/1784 Call Trace: <TASK> bzImage64_load+0x133/0xa00 __do_sys_kexec_file_load+0x2b3/0x5c0 do_syscall_64+0x81/0x610 entry_SYSCALL_64_after_hwframe+0x76/0x7e
[[email protected]: move helper to avoid forward declaration, per Baoquan]
Which versions are affected by CVE-2026-43289?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-43289?
Apply the vendor's patch.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-43289 being exploited?
There is no known exploitation of CVE-2026-43289 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2026-43289, DEBIAN-CVE-2026-43289, GHSA-3xcp-xr96-v535, ROOT-OS-DEBIAN-11-CVE-2026-43289, ROOT-OS-UBUNTU-2204-CVE-2026-43289, ROOT-OS-UBUNTU-2404-CVE-2026-43289 and 1 more.