CVE-2025-37749: debian debian_linux Out-of-bounds Read

Vulnerability summary

CVE-2025-37749 is a high (CVSS 8.2) Out-of-bounds Read vulnerability in debian debian_linux. EPSS estimates a 0.40% chance of exploitation in the next 30 days, higher than 32.5% of scored vulnerabilities.

Timeline

1. 01-05-2025
   PublishedVulnerability first disclosed.
2. 05-08-2026
   Last modifiedVulnerability information updated.

Description

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]

• CWE-125Out-of-bounds ReadThe product reads data past the end, or before the beginning, of the intended buffer.