CVE-2025-21768

In the Linux kernel, the following vulnerability has been resolved: net: ipv6: fix dst ref loops in rpl, seg6 and ioam6 lwtunnels Some lwtunnels have a dst cache for post-transformation dst. If the packet destination did not change we may end up recording a reference to the lwtunnel in its own cache, and the lwtunnel state will never be freed. Discovered by the ioam6.sh test, kmemleak was recently fixed to catch per-cpu memory leaks. I'm not sure if rpl and seg6 can actually hit this, but in principle I don't see why not.

CVSS v3 5.5 MEDIUM

5.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/4c0f200c7d06fedddde82209c099014d63f4a6c0	Patch
https://git.kernel.org/stable/c/5ab11a4e219e93b8b31a27f8ec98d42afadd8b7a	Patch
https://git.kernel.org/stable/c/92191dd1073088753821b862b791dcc83e558e07	Patch

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel:6.14:rc1::::::

History

No history.

Information

Published : 2025-02-27 03:15

Updated : 2025-10-28 20:28

NVD link : CVE-2025-21768

Mitre link : CVE-2025-21768

CVE.ORG link : CVE-2025-21768

JSON object : View

Products Affected

linux

linux_kernel

CWE

CWE-401

Missing Release of Memory after Effective Lifetime

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