Description
In the Linux kernel, the following vulnerability has been resolved: net: hinic: fix mailbox segment buffer overflow check_mbox_seq_id_and_seg_len() validates that seq_id does not exceed SEQ_ID_MAX_VAL (42) and seg_len does not exceed MBOX_SEG_LEN (48). However, this allows the last segment (seq_id=42) to carry a full 48-byte payload, writing to offset 42*48=2016 for 48 bytes (ending at byte 2064). The receive buffer is only MBOX_MAX_BUF_SZ (2048) bytes, resulting in a 16-byte heap buffer overflow. The hinic3 driver already handles this correctly by defining MBOX_LAST_SEG_MAX_LEN and rejecting the last segment when it exceeds the remaining buffer space. Apply the same fix to the hinic driver.
References8
- git.kernel.org/stable/c/513f7b16ed0cffae9348151c72bed17c7073096f
- git.kernel.org/stable/c/5d4d985957434867bbe85e4fa5e638f3e48ad522
- git.kernel.org/stable/c/72be1fd5d256dde748c0905c5e1749a119cad5bd
- git.kernel.org/stable/c/7cc974799fde846eda2d8f00ad4f8e1810eb0499
- git.kernel.org/stable/c/8de1e23bd91fe3a6683e4bc574e2d6bcb0eef920
- git.kernel.org/stable/c/9f6ad383901d0cb1c8ea5f7f3160fabfe1540eb5
- git.kernel.org/stable/c/c622bbc212207d7c6bbd69dd88f0c3a3f5853d16
- git.kernel.org/stable/c/eca54a092d5f7b497b458ff5a6f66d4f7bfb6674
Metrics
- CVSS 3.1
-
8.8
HIGH
Score source: CNA
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 4 · as of 9 November 2026
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