CVE-2026-74678
Published: August 27, 2026Last modified: August 27, 2026
Description
In the Linux kernel, the following vulnerability has been resolved: net: usb: ax88179_178a: fix skb leak in ax88179_tx_fixup() When the interface has NETIF_F_SG enabled and skb_linearize() fails in ax88179_tx_fixup(), the function returns NULL without freeing the skb. usbnet_start_xmit() treats a NULL return from tx_fixup() as a drop (info->flags does not set FLAG_MULTI_PACKET for this driver), jumping to the "drop" label where it does `if (skb) dev_kfree_skb_any(skb)`. Because tx_fixup() returned NULL, the local skb variable in usbnet_start_xmit() is NULL, so the original skb is never freed — a memory leak on every TX frame whose linearization fails (i.e. under memory pressure). Free the skb before returning, matching the error handling already used for the pskb_expand_head() failure path in the same function.
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score | 7.5 |
| Attack Vector | NETWORK |
| Attack complexity | LOW |
| Privileges required | NONE |
| User interaction | NONE |
| Scope | UNCHANGED |
| Confidentiality | NONE |
| Integrity impact | NONE |
| Availability impact | HIGH |
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
Status
| Product | Release | Package | Status |
|---|---|---|---|
| Alpaquita Linux | 23 LTS | linux-lts | Vulnerable (6.1.182-r0) |
| 25 LTS | linux-lts | Vulnerable (6.12.103-r0) | |
| Stream | linux-lts | Fixed (6.18.46-r0) |
References
- https://git.kernel.org/stable/c/1c63303659a2264bd55d9813df74cb4caeed5922
- https://git.kernel.org/stable/c/1f428e30947395d9b9aacee03e25a4e6cfcad7a4
- https://git.kernel.org/stable/c/2be5091fa693b9119ad25a8bb8c149d236a23ade
- https://git.kernel.org/stable/c/4039cd807a5a46dc5f7618fffae926b8ad8455eb
- https://git.kernel.org/stable/c/58733b1dd46bb231d9d279c132a20ee46da1b664
- https://git.kernel.org/stable/c/83a765cbd7b4d11b0b9fa1bb9d941ae911a2159b