Integer overflow in Linux
CVE-2026-23069
In the Linux kernel, the following vulnerability has been resolved: vsock/virtio: fix potential underflow in virtio_transport_get_credit() The credit calculation in virtio_transport_get_credit() uses unsigned arithmetic: ret = vvs->peer_buf_alloc - (vvs->tx_cnt - vvs->peer_fwd_cnt); If the peer shrinks its advertised buffer (peer_buf_alloc) while bytes are in flight, the subtraction can underflow and produce a large positive value, potentially allowing more data to be queued than the peer can handle. Reuse virtio_transport_has_space() which already handles this case and add a comment to make it clear why we are doing that. [Stefano: use virtio_transport_has_space() instead of duplicating the code] [Stefano: tweak the commit message]
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.
EPSS exploit prediction
EPSS: 0.001 (2.4th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 2nd percentile — 2.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.001 · newest: 0.001 · change: +0.000
Affected products
- Linux — versions 06a8fc78367d070720af960dcecec917d3ae5f3b, 4.8, 0
- Linux Kernel — versions 6.19
Weakness classification (CWE)
References
Frequently asked questions
- What is CVE-2026-23069?
- CVE-2026-23069 is a medium-severity vulnerability in Linux, classified under Integer Underflow. CVSS score: 5.5/10. Published 2026-02-04.
- How severe is CVE-2026-23069?
- Medium severity. CVSS v3 base score is 5.5 out of 10.