CVE-2026-43409: Linux kernel · kprobes: avoid crash when rmmod/insmod after ftrace killed
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 5.5 Medium · fixed in 6.8.0-1061.64~22.04.1 : update Linux kernel when convenient.
Data as of 26 Oct 2026, 17:16 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 1% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 6.8.0-1061.64~22.04.1, 6.8.0-1063.71~22.04.1, 6.8.0-1062.69~22.04.1 +30
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 8 May 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.04 LTSlinux-azure-fdepkg:deb/ubuntu/linux-azure-fde@7.0.0-1008.8?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 25.10linuxpkg:deb/ubuntu/linux?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-azure-fdepkg:deb/ubuntu/linux-azure-fde?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-gcppkg:deb/ubuntu/linux-gcp?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
A patch is available and should be applied to affected Linux kernel versions to prevent the kernel crash. The fix involves proper handling of the kprobe_ftrace_disabled flag in the kprobes subsystem. Systems running affected kernel versions should upgrade to patched versions as per vendor advisories. No additional mitigation is required beyond applying the official fix.
Description
A vulnerability in the Linux kernel's kprobes subsystem could cause a kernel crash when removing or inserting modules after ftrace has been killed due to errors. This occurs because kprobes does not properly handle the kprobe_ftrace_disabled flag set by ftrace_kill(), leading to a page fault and kernel oops. The issue has been resolved by adding a check for kprobe_ftrace_disabled in the __disarm_kprobe_ftrace() function to skip ftrace-related operations when disabled. The vulnerability affects specific Linux kernel versions and has a CVSS score of 5.5 with low severity. A patch is available to address this issue.
References
- ubuntu.com/security/CVE-2026-43409 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-43409 (opens in a new tab)
- git.kernel.org/linus/e113f0b46d19626ec15388bcb91432c9a4fd6261 (opens in a new tab)
- git.kernel.org/stable/c/8b6767e4141b2a42745b544d4555cf1614ba1a2d (opens in a new tab)
- git.kernel.org/stable/c/9edc79d664832a842012ad105b1521c1a3c35ab3 (opens in a new tab)
- git.kernel.org/stable/c/b0ca81616a010807e91fc31db9be242b96326adc (opens in a new tab)
- git.kernel.org/stable/c/cae928e3178c75602c21d67e21255d73e7e9ed4f (opens in a new tab)
- git.kernel.org/stable/c/e113f0b46d19626ec15388bcb91432c9a4fd6261 (opens in a new tab)
- ubuntu.com/security/notices/USN-8567-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8574-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8574-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8595-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8596-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8595-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8606-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8607-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8608-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8609-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8574-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-8595-3 (opens in a new tab)