Out-of-bounds Read in Linux

CVE-2025-37749

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]

Vulnerability class: Buffer Overflow

EPSS: 0.002 (7.5th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.2 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2025-37749?
CVE-2025-37749 is a high-severity vulnerability in Linux, classified under Out-of-bounds Read. CVSS score: 8.2/10. Published 2025-05-01.
How severe is CVE-2025-37749?
High severity. CVSS v3 base score is 8.2 out of 10.
Is CVE-2025-37749 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.