CVE-2023-53338
Unknown
Unknown - Not Provided
BaseFortify
Publication date: 2025-09-17
Last updated on: 2025-12-11
Assigner: kernel.org
Description
Description
In the Linux kernel, the following vulnerability has been resolved:
lwt: Fix return values of BPF xmit ops
BPF encap ops can return different types of positive values, such like
NET_RX_DROP, NET_XMIT_CN, NETDEV_TX_BUSY, and so on, from function
skb_do_redirect and bpf_lwt_xmit_reroute. At the xmit hook, such return
values would be treated implicitly as LWTUNNEL_XMIT_CONTINUE in
ip(6)_finish_output2. When this happens, skbs that have been freed would
continue to the neighbor subsystem, causing use-after-free bug and
kernel crashes.
To fix the incorrect behavior, skb_do_redirect return values can be
simply discarded, the same as tc-egress behavior. On the other hand,
bpf_lwt_xmit_reroute returns useful errors to local senders, e.g. PMTU
information. Thus convert its return values to avoid the conflict with
LWTUNNEL_XMIT_CONTINUE.
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| linux | linux_kernel | From 4.10 (inc) to 5.4.257 (exc) |
| linux | linux_kernel | From 5.5 (inc) to 5.10.195 (exc) |
| linux | linux_kernel | From 5.11 (inc) to 5.15.132 (exc) |
| linux | linux_kernel | From 5.16 (inc) to 6.1.53 (exc) |
| linux | linux_kernel | From 6.2 (inc) to 6.4.16 (exc) |
| linux | linux_kernel | From 6.5 (inc) to 6.5.3 (exc) |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-416 | The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer. |