Linux Kernel up to 7.1-rc2 ipv6 xfrm6_rcv_encap reference count

Summaryinfo

A vulnerability has been found in Linux Kernel up to 6.6.139/6.12.87/6.18.29/7.0.6/7.1-rc2 and classified as critical. The affected element is the function xfrm6_rcv_encap of the component ipv6. This manipulation causes reference count. This vulnerability is handled as CVE-2026-46172. There is not any exploit available. The affected component should be upgraded.

Detailsinfo

A vulnerability has been found in Linux Kernel up to 6.6.139/6.12.87/6.18.29/7.0.6/7.1-rc2 and classified as critical. Affected by this vulnerability is the function xfrm6_rcv_encap of the component ipv6. The manipulation with an unknown input leads to a reference count vulnerability. The CWE definition for the vulnerability is CWE-911. The product uses a reference count to manage a resource, but it does not update or incorrectly updates the reference count. As an impact it is known to affect availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: ipv6: xfrm6: release dst on error in xfrm6_rcv_encap() xfrm6_rcv_encap() performs an IPv6 route lookup when the skb does not already have a dst attached. ip6_route_input_lookup() returns a referenced dst entry even when the lookup resolves to an error route. If dst->error is set, xfrm6_rcv_encap() drops the skb without attaching the dst to the skb and without releasing the reference returned by the lookup. Repeated packets hitting this path therefore leak dst entries. Release the dst before jumping to the drop path.

It is possible to read the advisory at git.kernel.org. This vulnerability is known as CVE-2026-46172 since 05/13/2026. Technical details of the vulnerability are known, but there is no available exploit.

Upgrading to version 6.6.140, 6.12.88, 6.18.30, 7.0.7 or 7.1-rc3 eliminates this vulnerability. Applying the patch c2efc4956981066df2fef1cc77391b523db6d8e4/554c9b090c8ac5b1c5c507f4badf8d5d0c9c6e13/9d5047782f9bd2829e529df69209bf3232eb561f/6a5eec0a2a0e99ec9743cf8f1c4082178811d90a/bc0fcb9823cd0894934cf968b525c575833d7078 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.

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Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.6.139
• 6.12.0
• 6.12.1
• 6.12.2
• 6.12.3
• 6.12.4
• 6.12.5
• 6.12.6
• 6.12.7
• 6.12.8
• 6.12.9
• 6.12.10
• 6.12.11
• 6.12.12
• 6.12.13
• 6.12.14
• 6.12.15
• 6.12.16
• 6.12.17
• 6.12.18
• 6.12.19
• 6.12.20
• 6.12.21
• 6.12.22
• 6.12.23
• 6.12.24
• 6.12.25
• 6.12.26
• 6.12.27
• 6.12.28
• 6.12.29
• 6.12.30
• 6.12.31
• 6.12.32
• 6.12.33
• 6.12.34
• 6.12.35
• 6.12.36
• 6.12.37
• 6.12.38
• 6.12.39
• 6.12.40
• 6.12.41
• 6.12.42
• 6.12.43
• 6.12.44
• 6.12.45
• 6.12.46
• 6.12.47
• 6.12.48
• 6.12.49
• 6.12.50
• 6.12.51
• 6.12.52
• 6.12.53
• 6.12.54
• 6.12.55
• 6.12.56
• 6.12.57
• 6.12.58
• 6.12.59
• 6.12.60
• 6.12.61
• 6.12.62
• 6.12.63
• 6.12.64
• 6.12.65
• 6.12.66
• 6.12.67
• 6.12.68
• 6.12.69
• 6.12.70
• 6.12.71
• 6.12.72
• 6.12.73
• 6.12.74
• 6.12.75
• 6.12.76
• 6.12.77
• 6.12.78
• 6.12.79
• 6.12.80
• 6.12.81
• 6.12.82
• 6.12.83
• 6.12.84
• 6.12.85
• 6.12.86
• 6.12.87
• 6.18.0
• 6.18.1
• 6.18.2
• 6.18.3
• 6.18.4
• 6.18.5
• 6.18.6
• 6.18.7
• 6.18.8
• 6.18.9
• 6.18.10
• 6.18.11
• 6.18.12
• 6.18.13
• 6.18.14
• 6.18.15
• 6.18.16
• 6.18.17
• 6.18.18
• 6.18.19
• 6.18.20
• 6.18.21
• 6.18.22
• 6.18.23
• 6.18.24
• 6.18.25
• 6.18.26
• 6.18.27
• 6.18.28
• 6.18.29
• 7.0.0
• 7.0.1
• 7.0.2
• 7.0.3
• 7.0.4
• 7.0.5
• 7.0.6
• 7.1-rc1
• 7.1-rc2

License

• open-source

Website

• Vendor: https://www.kernel.org/

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Entryinfo

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