CVE-2026-23069

Summary

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]

Affected Software

VendorProductVersion RangeStatus
LinuxLinux06a8fc78367d070720af960dcecec917d3ae5f3b < d96de882d6b99955604669d962ae14e94b66a551affected
LinuxLinux06a8fc78367d070720af960dcecec917d3ae5f3b < 02f9af192b98d15883c70dd41ac76d1b0217c899affected
LinuxLinux06a8fc78367d070720af960dcecec917d3ae5f3b < d05bc313788f0684b27f0f5b60c52a844669b542affected
LinuxLinux06a8fc78367d070720af960dcecec917d3ae5f3b < ec0f1b3da8061be3173d1c39faaf9504f91942c3affected
LinuxLinux06a8fc78367d070720af960dcecec917d3ae5f3b < 3ef3d52a1a9860d094395c7a3e593f3aa26ff012affected
LinuxLinux4.8affected
LinuxLinux0 < 4.8unaffected
LinuxLinux6.1.162 <= 6.1.*unaffected
LinuxLinux6.6.122 <= 6.6.*unaffected
LinuxLinux6.12.68 <= 6.12.*unaffected
LinuxLinux6.18.8 <= 6.18.*unaffected
LinuxLinux6.19 <= *unaffected

Weaknesses

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: partial

References