CVE-2026-43339: Linux kernel · ipv6: prevent possible UaF in addrconf_permanent_addr()
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.8 High : upgrade to 7.0.0-1006.6 soon.
Data as of 26 Oct 2026, 14:05 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 4% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 7.0.0-1006.6
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/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 the Ubuntu linux-nvidia package to 7.0.0-1006.6.
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 26.04 LTSlinux-nvidiapkg:deb/ubuntu/linux-nvidia@7.0.0-1006.6?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 25.10linuxpkg:deb/ubuntu/linux@6.17.0-40.40?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-awspkg:deb/ubuntu/linux-aws@6.17.0-1019.19?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-azurepkg:deb/ubuntu/linux-azure@6.17.0-1020.20?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-azure-fdepkg:deb/ubuntu/linux-azure-fde@6.17.0-1017.17?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-azure kernel versions. The vendor advisory from Ubuntu confirms that this issue has been fixed in updated kernel packages. Users should update to the fixed kernel versions to mitigate this vulnerability.
Description
A use-after-free (UaF) vulnerability was identified and resolved in the Linux kernel's IPv6 addrconf_permanent_addr() function. The issue involved a delayed warning message that accessed IPv6 data after it might have been deleted, potentially leading to a UaF condition. This vulnerability affects specific linux-azure kernel versions. A patch is available that reorders the code to prevent the UaF and moves the warning outside the lock for proper protection.
References
- ubuntu.com/security/CVE-2026-43339 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-43339 (opens in a new tab)
- git.kernel.org/linus/fd63f185979b047fb22a0dfc6bd94d0cab6a6a70 (opens in a new tab)
- git.kernel.org/stable/c/25357b670afb5b517096da783abaa5cc4bf8359e (opens in a new tab)
- git.kernel.org/stable/c/2d88ed7fa000e19c2dc0fa31b3a849e3f5bca5c1 (opens in a new tab)
- git.kernel.org/stable/c/3cd4efb5df72843dfac892d0b3c7a4a8bd926b65 (opens in a new tab)
- git.kernel.org/stable/c/7bfafa1b0cd582983ebec6bb20f0a435528fe567 (opens in a new tab)
- git.kernel.org/stable/c/7d9f2f4aabd116ca68fbdab5d8fb8dac74c2ea1e (opens in a new tab)
- git.kernel.org/stable/c/bacc7f31085c9820922f00bc7d79756ffa13123a (opens in a new tab)
- git.kernel.org/stable/c/eec49a33611f20336b357b3953df44f1a02049e8 (opens in a new tab)
- git.kernel.org/stable/c/fd63f185979b047fb22a0dfc6bd94d0cab6a6a70 (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-8575-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8576-1 (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-8575-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8576-2 (opens in a new tab)