CVE-2023-53338
published 2025-09-17CVE-2023-53338: 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…
PriorityP338high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.19%
9.4th percentile
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.
Affected
19 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | linux | < linux 6.1.55-1 (bookworm) | linux 6.1.55-1 (bookworm) |
| linux | linux | — | — |
| linux | linux | >= 3a0af8fd61f90920f6fa04e4f1e9a6a73c1b4fd2 < 67f8f2bae8e7ac72e09def2b667e44704c4d1ee1 | 67f8f2bae8e7ac72e09def2b667e44704c4d1ee1 |
| linux | linux | >= 3a0af8fd61f90920f6fa04e4f1e9a6a73c1b4fd2 < a97f221651fcdc891166e9bc270e3d9bfa5a0080 | a97f221651fcdc891166e9bc270e3d9bfa5a0080 |
| linux | linux | >= 3a0af8fd61f90920f6fa04e4f1e9a6a73c1b4fd2 < e3f647e4b642f9f6d32795a16f92c116c138d2af | e3f647e4b642f9f6d32795a16f92c116c138d2af |
| linux | linux | >= 3a0af8fd61f90920f6fa04e4f1e9a6a73c1b4fd2 < 065d5f17096ec9161180e2c890afdff4dc6125f2 | 065d5f17096ec9161180e2c890afdff4dc6125f2 |
| linux | linux | >= 3a0af8fd61f90920f6fa04e4f1e9a6a73c1b4fd2 < d68c17402442f5f494a2c3ebde5cb82f6aa9160a | d68c17402442f5f494a2c3ebde5cb82f6aa9160a |
| linux | linux | >= 3a0af8fd61f90920f6fa04e4f1e9a6a73c1b4fd2 < 65583f9e070db7bece20710cfa2e3daeb0b831d9 | 65583f9e070db7bece20710cfa2e3daeb0b831d9 |
| linux | linux | >= 3a0af8fd61f90920f6fa04e4f1e9a6a73c1b4fd2 < 29b22badb7a84b783e3a4fffca16f7768fb31205 | 29b22badb7a84b783e3a4fffca16f7768fb31205 |
| linux | linux_kernel | >= 0 < 5.10.197-1 | 5.10.197-1 |
| linux | linux_kernel | >= 0 < 6.1.55-1 | 6.1.55-1 |
| linux | linux_kernel | >= 0 < 6.5.3-1 | 6.5.3-1 |
| linux | linux_kernel | >= 0 < 6.5.3-1 | 6.5.3-1 |
| linux | linux_kernel | >= 4.10 < 5.4.257 | 5.4.257 |
| linux | linux_kernel | >= 5.11 < 5.15.132 | 5.15.132 |
| linux | linux_kernel | >= 5.16 < 6.1.53 | 6.1.53 |
| linux | linux_kernel | >= 5.5 < 5.10.195 | 5.10.195 |
| linux | linux_kernel | >= 6.2 < 6.4.16 | 6.4.16 |
| linux | linux_kernel | >= 6.5 < 6.5.3 | 6.5.3 |
CVSS provenance
nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
osv7.8HIGH
vendor_debian7.8HIGH
vendor_redhat7.8HIGH
Stop checking back — get the weekly exploitation signal.
Every Monday: what got weaponized or added to CISA KEV in the last seven days — each CVE cross-linked to its PoC, Nuclei template, and detection rule. Free, one email a week, unsubscribe in one click.
OSV
CVE-2023-53338: 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
osv·2025-09-17·CVSS 7.8
CVE-2023-53338 [HIGH] CVE-2023-53338: 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
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 th
GHSA
GHSA-wqfp-wxf7-9vr7: 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
ghsa_unreviewed·2025-09-17
CVE-2023-53338 [HIGH] CWE-416 GHSA-wqfp-wxf7-9vr7: 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
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
Red Hat
kernel: lwt: Fix return values of BPF xmit ops
vendor_redhat·2025-09-17·CVSS 7.8
CVE-2023-53338 [HIGH] CWE-253 kernel: lwt: Fix return values of BPF xmit ops
kernel: lwt: Fix return values of BPF xmit ops
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
informa
Debian
CVE-2023-53338: linux - In the Linux kernel, the following vulnerability has been resolved: lwt: Fix re...
vendor_debian·2023·CVSS 7.8
CVE-2023-53338 [HIGH] CVE-2023-53338: linux - In the Linux kernel, the following vulnerability has been resolved: lwt: Fix re...
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 th
No detection rules found.
No public exploits indexed.
https://git.kernel.org/stable/c/065d5f17096ec9161180e2c890afdff4dc6125f2https://git.kernel.org/stable/c/29b22badb7a84b783e3a4fffca16f7768fb31205https://git.kernel.org/stable/c/65583f9e070db7bece20710cfa2e3daeb0b831d9https://git.kernel.org/stable/c/67f8f2bae8e7ac72e09def2b667e44704c4d1ee1https://git.kernel.org/stable/c/a97f221651fcdc891166e9bc270e3d9bfa5a0080https://git.kernel.org/stable/c/d68c17402442f5f494a2c3ebde5cb82f6aa9160ahttps://git.kernel.org/stable/c/e3f647e4b642f9f6d32795a16f92c116c138d2af
2025-09-17
Published