Integer overflow in Linux

CVE-2024-57843

In the Linux kernel, the following vulnerability has been resolved: virtio-net: fix overflow inside virtnet_rq_alloc When the frag just got a page, then may lead to regression on VM. Specially if the sysctl net.core.high_order_alloc_disable value is 1, then the frag always get a page when do refill. Which could see reliable crashes or scp failure (scp a file 100M in size to VM). The issue is that the virtnet_rq_dma takes up 16 bytes at the beginning of a new frag. When the frag size is larger than PAGE_SIZE, everything is fine. However, if the frag is only one page and the total size of the buffer and virtnet_rq_dma is larger than one page, an overflow may occur. The commit f9dac92ba908 ("virtio_ring: enable premapped mode whatever use_dma_api") introduced this problem. And we reverted some commits to fix this in last linux version. Now we try to enable it and fix this bug directly. Here, when the frag size is not enough, we reduce the buffer len to fix this problem.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.004 (33.4th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 33rd percentile — 33.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2024-57843: held from 0.004 to 0.004.

EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2024-57843?
CVE-2024-57843 is a critical-severity vulnerability in Linux, classified under Integer Underflow. CVSS score: 9.8/10. Published 2025-01-11.
How severe is CVE-2024-57843?
Critical severity. CVSS v3 base score is 9.8 out of 10.