CVE-2023-6693: Qemu: virtio-net: stack buffer overflow in virtio_net_flush_tx()

Vulnerability summary

CVE-2023-6693 is a medium (CVSS 5.3) Stack-based Buffer Overflow vulnerability in fedoraproject fedora. EPSS estimates a 0.33% chance of exploitation in the next 30 days, higher than 26.2% of scored vulnerabilities.

Timeline

1. 02-01-2024
   PublishedVulnerability first disclosed.
2. 25-02-2026
   Last modifiedVulnerability information updated.

Description

A stack based buffer overflow was found in the virtio-net device of QEMU. This issue occurs when flushing TX in the virtio_net_flush_tx function if guest features VIRTIO_NET_F_HASH_REPORT, VIRTIO_F_VERSION_1 and VIRTIO_NET_F_MRG_RXBUF are enabled. This could allow a malicious user to overwrite local variables allocated on the stack. Specifically, the `out_sg` variable could be used to read a part of process memory and send it to the wire, causing an information leak.

• CWE-121Stack-based Buffer OverflowThe product writes past the end of a buffer that was allocated on the stack.
• CWE-787Out-of-bounds WriteThe product writes data past the end, or before the beginning, of the intended buffer.