cbcvebase.
CVE-2024-35839
published 2024-05-17

CVE-2024-35839: In the Linux kernel, the following vulnerability has been resolved: netfilter: bridge: replace physindev with physinif in nf_bridge_info An skb can be added to…

PriorityP419medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.24%
14.9th percentile
In the Linux kernel, the following vulnerability has been resolved: netfilter: bridge: replace physindev with physinif in nf_bridge_info An skb can be added to a neigh->arp_queue while waiting for an arp reply. Where original skb's skb->dev can be different to neigh's neigh->dev. For instance in case of bridging dnated skb from one veth to another, the skb would be added to a neigh->arp_queue of the bridge. As skb->dev can be reset back to nf_bridge->physindev and used, and as there is no explicit mechanism that prevents this physindev from been freed under us (for instance neigh_flush_dev doesn't cleanup skbs from different device's neigh queue) we can crash on e.g. this stack: arp_process neigh_update skb = __skb_dequeue(&neigh->arp_queue) neigh_resolve_output(..., skb) ... br_nf_dev_xmit br_nf_pre_routing_finish_bridge_slow skb->dev = nf_bridge->physindev br_handle_frame_finish Let's use plain ifindex instead of net_device link. To peek into the original net_device we will use dev_get_by_index_rcu(). Thus either we get device and are safe to use it or we don't get it and drop skb.

Affected

15 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 6.1.76-1 (bookworm)linux 6.1.76-1 (bookworm)
linuxlinux
linuxlinux>= c4e70a87d975d1f561a00abfe2d3cefa2a486c95 < 7ae19ee81ca56b13c50a78de6c47d5b8fdc9d97b7ae19ee81ca56b13c50a78de6c47d5b8fdc9d97b
linuxlinux>= c4e70a87d975d1f561a00abfe2d3cefa2a486c95 < 9325e3188a9cf3f69fc6f32af59844bbc5b905479325e3188a9cf3f69fc6f32af59844bbc5b90547
linuxlinux>= c4e70a87d975d1f561a00abfe2d3cefa2a486c95 < 544add1f1cfb78c3dfa3e6edcf4668f6be5e730c544add1f1cfb78c3dfa3e6edcf4668f6be5e730c
linuxlinux>= c4e70a87d975d1f561a00abfe2d3cefa2a486c95 < 9874808878d9eed407e3977fd11fee49de1e1d869874808878d9eed407e3977fd11fee49de1e1d86
linuxlinux_kernel>= 0 < 6.1.76-16.1.76-1
linuxlinux_kernel>= 0 < 6.6.15-16.6.15-1
linuxlinux_kernel>= 0 < 6.6.15-16.6.15-1
linuxlinux_kernel>= 4.2 < 6.1.756.1.75
linuxlinux_kernel>= 6.2 < 6.6.146.6.14
linuxlinux_kernel>= 6.7 < 6.7.26.7.2
msrccbl2_kernel_5.15.186.1-1_on_cbl_mariner_2.0
msrccbl2_kernel_5.15.200.1-1_on_cbl_mariner_2.0
msrccbl2_kernel_5.15.202.1-1_on_cbl_mariner_2.0

CVSS provenance

nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv7.5HIGH
vendor_ubuntu6.5MEDIUM
vendor_debian5.5MEDIUM
vendor_msrc5.5MEDIUM
vendor_redhat5.5MEDIUM
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