Linux Kernel up to 5.16.12 ipv6 ipv6_mc_down allocation of resources

Summaryinfo

A vulnerability classified as problematic was found in Linux Kernel up to 5.16.12. Affected by this vulnerability is the function ipv6_mc_down of the component ipv6. Executing a manipulation can lead to allocation of resources. This vulnerability is handled as CVE-2022-48910. There is not any exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in Linux Kernel up to 5.16.12. It has been declared as problematic. This vulnerability affects the function ipv6_mc_down of the component ipv6. The manipulation with an unknown input leads to a allocation of resources vulnerability. The CWE definition for the vulnerability is CWE-770. The product allocates a reusable resource or group of resources on behalf of an actor without imposing any restrictions on the size or number of resources that can be allocated, in violation of the intended security policy for that actor. The impact remains unknown. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: net: ipv6: ensure we call ipv6_mc_down() at most once There are two reasons for addrconf_notify() to be called with NETDEV_DOWN: either the network device is actually going down, or IPv6 was disabled on the interface. If either of them stays down while the other is toggled, we repeatedly call the code for NETDEV_DOWN, including ipv6_mc_down(), while never calling the corresponding ipv6_mc_up() in between. This will cause a new entry in idev->mc_tomb to be allocated for each multicast group the interface is subscribed to, which in turn leaks one struct ifmcaddr6 per nontrivial multicast group the interface is subscribed to. The following reproducer will leak at least $n objects: ip addr add ff2e::4242/32 dev eth0 autojoin sysctl -w net.ipv6.conf.eth0.disable_ipv6=1 for i in $(seq 1 $n); do ip link set up eth0; ip link set down eth0 done Joining groups with IPV6_ADD_MEMBERSHIP (unprivileged) or setting the sysctl net.ipv6.conf.eth0.forwarding to 1 (=> subscribing to ff02::2) can also be used to create a nontrivial idev->mc_list, which will the leak objects with the right up-down-sequence. Based on both sources for NETDEV_DOWN events the interface IPv6 state should be considered: - not ready if the network interface is not ready OR IPv6 is disabled for it - ready if the network interface is ready AND IPv6 is enabled for it The functions ipv6_mc_up() and ipv6_down() should only be run when this state changes. Implement this by remembering when the IPv6 state is ready, and only run ipv6_mc_down() if it actually changed from ready to not ready. The other direction (not ready -> ready) already works correctly, as: - the interface notification triggered codepath for NETDEV_UP / NETDEV_CHANGE returns early if ipv6 is disabled, and - the disable_ipv6=0 triggered codepath skips fully initializing the interface as long as addrconf_link_ready(dev) returns false - calling ipv6_mc_up() repeatedly does not leak anything

The advisory is available at git.kernel.org. This vulnerability was named CVE-2022-48910 since 08/21/2024. Technical details are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 211811 (EulerOS 2.0 SP12 : kernel (EulerOS-SA-2024-2923)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 4.9.313, 4.14.278, 5.4.193, 5.10.104, 5.15.27 or 5.16.13 eliminates this vulnerability. Applying the patch 9a8736b2da28/c71bf3229f9e/9588ac2eddc2/f4c63b24dea9/b11781515208/72124e65a70b/9995b408f17f 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 vulnerability database at Tenable (211811). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 4.9.312
• 4.14.277
• 5.4.192
• 5.10.103
• 5.15.0
• 5.15.1
• 5.15.2
• 5.15.3
• 5.15.4
• 5.15.5
• 5.15.6
• 5.15.7
• 5.15.8
• 5.15.9
• 5.15.10
• 5.15.11
• 5.15.12
• 5.15.13
• 5.15.14
• 5.15.15
• 5.15.16
• 5.15.17
• 5.15.18
• 5.15.19
• 5.15.20
• 5.15.21
• 5.15.22
• 5.15.23
• 5.15.24
• 5.15.25
• 5.15.26
• 5.16.0
• 5.16.1
• 5.16.2
• 5.16.3
• 5.16.4
• 5.16.5
• 5.16.6
• 5.16.7
• 5.16.8
• 5.16.9
• 5.16.10
• 5.16.11
• 5.16.12

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

• 🔍
• 🔍
• 🔍

CPE 2.2info

• 🔍
• 🔍
• 🔍

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Discussion