Linux Kernel up to 6.19.11 addrconf_permanent_addr use after free

CVSS Meta Temp Score
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CTI Interest Score
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7.7$0-$5k0.00

Summaryinfo

A vulnerability was found in Linux Kernel up to 6.19.11 and classified as critical. This affects the function addrconf_permanent_addr. Executing a manipulation can lead to use after free. This vulnerability appears as CVE-2026-43339. There is no available exploit. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability has been found in Linux Kernel up to 6.19.11 and classified as critical. This vulnerability affects the function addrconf_permanent_addr. The manipulation with an unknown input leads to a use after free vulnerability. The CWE definition for the vulnerability is CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: ipv6: prevent possible UaF in addrconf_permanent_addr() The mentioned helper try to warn the user about an exceptional condition, but the message is delivered too late, accessing the ipv6 after its possible deletion. Reorder the statement to avoid the possible UaF; while at it, place the warning outside the idev->lock as it needs no protection.

The advisory is shared for download at git.kernel.org. This vulnerability was named CVE-2026-43339 since 05/01/2026. The exploitation appears to be easy. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 06/18/2026).

The vulnerability scanner Nessus provides a plugin with the ID 313396 (Linux Distros Unpatched Vulnerability : CVE-2026-43339), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.10.253, 5.15.203, 6.1.168, 6.6.134, 6.12.81, 6.18.22 or 6.19.12 eliminates this vulnerability. Applying the patch eec49a33611f20336b357b3953df44f1a02049e8/bacc7f31085c9820922f00bc7d79756ffa13123a/7bfafa1b0cd582983ebec6bb20f0a435528fe567/7d9f2f4aabd116ca68fbdab5d8fb8dac74c2ea1e/25357b670afb5b517096da783abaa5cc4bf8359e/3cd4efb5df72843dfac892d0b3c7a4a8bd926b65/2d88ed7fa000e19c2dc0fa31b3a849e3f5bca5c1/fd63f185979b047fb22a0dfc6bd94d0cab6a6a70 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (313396) and CERT Bund (WID-SEC-2026-1454). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Affected

  • Google Container-Optimized OS
  • Debian Linux
  • Red Hat Enterprise Linux
  • SUSE Linux
  • Oracle Linux
  • SUSE openSUSE
  • RESF Rocky Linux
  • Microsoft Azure Linux
  • Open Source Linux Kernel

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.9
VulDB Meta Temp Score: 7.7

VulDB Base Score: 8.0
VulDB Temp Score: 7.6
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 7.8
CNA Vector (Linux): 🔒

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Use after free
CWE: CWE-416 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 313396
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2026-43339

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 5.10.253/5.15.203/6.1.168/6.6.134/6.12.81/6.18.22/6.19.12
Patch: eec49a33611f20336b357b3953df44f1a02049e8/bacc7f31085c9820922f00bc7d79756ffa13123a/7bfafa1b0cd582983ebec6bb20f0a435528fe567/7d9f2f4aabd116ca68fbdab5d8fb8dac74c2ea1e/25357b670afb5b517096da783abaa5cc4bf8359e/3cd4efb5df72843dfac892d0b3c7a4a8bd926b65/2d88ed7fa000e19c2dc0fa31b3a849e3f5bca5c1/fd63f185979b047fb22a0dfc6bd94d0cab6a6a70

Timelineinfo

05/01/2026 CVE reserved
05/08/2026 +7 days Advisory disclosed
05/08/2026 +0 days VulDB entry created
06/18/2026 +41 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-43339 (🔒)
GCVE (CVE): GCVE-0-2026-43339
GCVE (VulDB): GCVE-100-362128
CERT Bund: WID-SEC-2026-1454 - Linux Kernel: Mehrere Schwachstellen

Entryinfo

Created: 05/08/2026 16:32
Updated: 06/18/2026 23:32
Changes: 05/08/2026 16:32 (58), 05/09/2026 07:32 (2), 05/18/2026 07:22 (11), 06/18/2026 23:32 (7)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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