CVE-2026-43071: Linux kernel · Out-of-bounds Read
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 9.1 Critical · fixed in 5.15.0-1111.118~20.04.1 : patch Linux kernel as a priority.
Data as of 26 Oct 2026, 14:05 UTC
- EPSS
- 0.4% chance of exploitation in 30 days – higher than 39% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 5.15.0-1111.118~20.04.1, 5.15.0-1116.125~20.04.1, 5.15.0-1111.121~20.04.1 +76
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 5 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 LTSlinuxpkg:deb/ubuntu/linux@7.0.0-27.27?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-awspkg:deb/ubuntu/linux-aws@7.0.0-1008.8?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-azurepkg:deb/ubuntu/linux-azure@7.0.0-1009.9?arch=source&distro=resoluteOther threats | 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 26.04 LTSlinux-gcppkg:deb/ubuntu/linux-gcp@7.0.0-1007.7?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-ibmpkg:deb/ubuntu/linux-ibm@7.0.0-1009.9?arch=source&distro=resoluteOther 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 fix is available that limits the minimal number of dentry_hashtable buckets to two, preventing the out-of-bounds read. Users should apply the official Linux kernel updates that include this patch. The Ubuntu advisory USN-8488-1 references this and other kernel fixes; applying these updates will remediate the vulnerability.
Description
A critical out-of-bounds read vulnerability in the Linux kernel's dcache subsystem was resolved by limiting the minimal number of dentry_hashtable buckets to two. The flaw occurs when the user sets 'dhash_entries=1', causing an invalid memory access due to improper calculation of the hash shift and resulting in a kernel crash. This vulnerability is identified as CVE-2026-43071 and affects specific Linux kernel versions. The issue has been fixed by ensuring at least two buckets are allocated, preventing the out-of-bounds read.
References
- ubuntu.com/security/CVE-2026-43071 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-43071 (opens in a new tab)
- git.kernel.org/linus/f08fe8891c3eeb63b73f9f1f6d97aa629c821579 (opens in a new tab)
- ubuntu.com/security/notices/USN-8488-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8490-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8491-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8492-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8493-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8488-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8492-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8497-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8498-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8499-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8493-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8507-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8508-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8492-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-8490-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8492-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-8492-5 (opens in a new tab)
- nvd.nist.gov/vuln/detail/CVE-2026-43071 (opens in a new tab)
- cert-portal.siemens.com/productcert/html/ssa-019113.html (opens in a new tab)
- git.kernel.org/stable/c/277cedabb0ab86baae83fa58218be13c6d3e5526 (opens in a new tab)
- git.kernel.org/stable/c/426ef05e82ee52c8d0e95fc0808b7383d8352d73 (opens in a new tab)
- git.kernel.org/stable/c/45b06bb5ea96f75ad81d7ef446f832ea6b0026fe (opens in a new tab)
- git.kernel.org/stable/c/5718df131ab78897a9dd1f2e71c3ba732d4392af (opens in a new tab)
- git.kernel.org/stable/c/755b40903eff563768d4d96fd4ef51ec48adde3b (opens in a new tab)
- git.kernel.org/stable/c/ddd57ebce245f9c7e2f6902a6c087d6186d2385d (opens in a new tab)
- git.kernel.org/stable/c/f08fe8891c3eeb63b73f9f1f6d97aa629c821579 (opens in a new tab)