CVE-2025-39673
published 2025-09-05CVE-2025-39673: In the Linux kernel, the following vulnerability has been resolved: ppp: fix race conditions in ppp_fill_forward_path ppp_fill_forward_path() has two race…
medium4.7CVSS 3.1
AVLACHPRLUINSUCNINAH
In the Linux kernel, the following vulnerability has been resolved:
ppp: fix race conditions in ppp_fill_forward_path
ppp_fill_forward_path() has two race conditions:
1. The ppp->channels list can change between list_empty() and
list_first_entry(), as ppp_lock() is not held. If the only channel
is deleted in ppp_disconnect_channel(), list_first_entry() may
access an empty head or a freed entry, and trigger a panic.
2. pch->chan can be NULL. When ppp_unregister_channel() is called,
pch->chan is set to NULL before pch is removed from ppp->channels.
Fix these by using a lockless RCU approach:
- Use list_first_or_null_rcu() to safely test and access the first list
entry.
- Convert list modifications on ppp->channels to their RCU variants and
add synchronize_net() after removal.
- Check for a NULL pch->chan before dereferencing it.
Affected
33 ranges· showing 25
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | debian_linux | — | — |
| debian | linux | < linux 6.1.153-1 (bookworm) | linux 6.1.153-1 (bookworm) |
| debian | linux-6.1 | < linux 6.1.153-1 (bookworm) | linux 6.1.153-1 (bookworm) |
| linux | linux | — | — |
| linux | linux | >= f6efc675c9dd8d93f826b79ae7e33e03301db609 < 9a1969fbffc1f1900d92d7594b1b7d8d72ef3dc7 | 9a1969fbffc1f1900d92d7594b1b7d8d72ef3dc7 |
| linux | linux | >= f6efc675c9dd8d93f826b79ae7e33e03301db609 < 0f1630be6fcca3f0c63e4b242ad202e5cde28a40 | 0f1630be6fcca3f0c63e4b242ad202e5cde28a40 |
| linux | linux | >= f6efc675c9dd8d93f826b79ae7e33e03301db609 < ca18d751bcc9faf5b7e82e9fae1223d103928181 | ca18d751bcc9faf5b7e82e9fae1223d103928181 |
| linux | linux | >= f6efc675c9dd8d93f826b79ae7e33e03301db609 < 94731cc551e29511d85aa8dec61a6c071b1f2430 | 94731cc551e29511d85aa8dec61a6c071b1f2430 |
| linux | linux | >= f6efc675c9dd8d93f826b79ae7e33e03301db609 < f97f6475fdcb3c28ff3c55cc4b7bde632119ec08 | f97f6475fdcb3c28ff3c55cc4b7bde632119ec08 |
| linux | linux | >= f6efc675c9dd8d93f826b79ae7e33e03301db609 < 0417adf367a0af11adf7ace849af4638cfb573f7 | 0417adf367a0af11adf7ace849af4638cfb573f7 |
| linux | linux_kernel | — | — |
| linux | linux_kernel | >= 0 < 6.1.153-1 | 6.1.153-1 |
| linux | linux_kernel | >= 0 < 6.12.48-1 | 6.12.48-1 |
| linux | linux_kernel | >= 0 < 6.16.5-1 | 6.16.5-1 |
| linux | linux_kernel | >= 0 < 5.15.0-163.173 | 5.15.0-163.173 |
| linux | linux_kernel | >= 0 < 6.8.0-100.100 | 6.8.0-100.100 |
| linux | linux_kernel | >= 5.13 < 5.15.190 | 5.15.190 |
| linux | linux_kernel | >= 5.16 < 6.1.149 | 6.1.149 |
| linux | linux_kernel | >= 6.13 < 6.16.4 | 6.16.4 |
| linux | linux_kernel | >= 6.2 < 6.6.103 | 6.6.103 |
| linux | linux_kernel | >= 6.7 < 6.12.44 | 6.12.44 |
| msrc | azl3_kernel_6.6.96.2-1_on_azure_linux_3.0 | — | — |
| msrc | azl3_kernel_6.6.96.2-2_on_azure_linux_3.0 | — | — |
| msrc | cbl2_kernel_5.15.186.1-1_on_cbl_mariner_2.0 | — | — |
| ubuntu | linux-aws | — | — |
CVSS provenance
nvdv3.14.7MEDIUMCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
osv5.5MEDIUM