CVE-2025-37749: Debian Linux

High severity, CVSS 7.1. EPSS: 0.4% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: net: ppp: Add bound checking for skb data on ppp_sync_txmung Ensure we have enough data in linear buffer from skb before accessing initial bytes. This prevents potential out-of-bounds accesses when processing short packets. When ppp_sync_txmung receives an incoming package with an empty payload: (remote) gef➤ p *(struct pppoe_hdr *) (skb->head + skb->network_header) $18 = { type = 0x1, ver = 0x1, code = 0x0, sid = 0x2, length = 0x0, tag = 0xffff8880371cdb96 } from the skb struct (trimmed) tail = 0x16, end = 0x140, head = 0xffff88803346f400 "4", data = 0xffff88803346f416 ":\377", truesize = 0x380, len = 0x0, data_len = 0x0, mac_len = 0xe, hdr_len = 0x0, it is not safe to access data[2]. [pabeni@redhat.com: fixed subj typo]

Affected products

• Debian Debian Linux: version 11.0 only
• Linux Linux Kernel: from 2.6.13, before 5.4.293 (fixed in 5.4.293); from 5.5, before 5.10.237 (fixed in 5.10.237); from 5.11, before 5.15.181 (fixed in 5.15.181); from 5.16, before 6.1.135 (fixed in 6.1.135); from 6.2, before 6.6.88 (fixed in 6.6.88); from 6.7, before 6.12.24 (fixed in 6.12.24); …

Published 2025-05-01. Last modified 2026-07-30.