CVE Catalog

CVE-2025-40046

HighCVSS 8.6
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.33%

25th percentile - higher than 25% of all known CVEs

Summary

In the Linux kernel, the io_uring/zcrx subsystem has a bug causing overshooting of the receive limit. Double counting of buffers in frag lists allows a request to receive more data than requested.

Risk Assessment

This could lead to buffer overflow or unexpected behavior in applications using zero-copy RX, potentially allowing an attacker to read out-of-bounds data.

Recommendation

Update the Linux kernel to a version containing the fix that corrects the double counting in io_zcrx_recv_skb().

Other vulnerabilities in Linux kernel

See all
Original NVD description (English source)

In the Linux kernel, the following vulnerability has been resolved: io_uring/zcrx: fix overshooting recv limit It's reported that sometimes a zcrx request can receive more than was requested. It's caused by io_zcrx_recv_skb() adjusting desc->count for all received buffers including frag lists, but then doing recursive calls to process frag list skbs, which leads to desc->count double accounting and underflow.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS