In the Linux kernel, the following vulnerability has been resolved: io_uring/cmd: fix iovec leak when the async cmd is not recycled An io_async_cmd carries an iovec array in ->vec.iovec, allocated when the vec has to grow and kept across recycling through ctx->cmd_cache. On two paths nothing frees it and io_clean_op()'s kfree(req->async_data) drops the io_async_cmd without it. io_req_uring_cleanup() clears the async data flags only when io_alloc_cache_put() succeeds, and the cache holds IO_ALLOC_CACHE_MAX == 128 entries, so once it is full the put fails and the vec is left behind. An NVMe passthrough workload gets there without doing anything unusual: nvme_uring_cmd_io() returns -EIOCBQUEUED, so the io_async_cmd stays attached for the lifetime of the command and the live object count tracks the queue depth. Above 128 the puts start failing. ->cleanup is the last chance to free an inherited vec, since io_req_uring_cleanup() returns early for an io-wq issued command and is not called at all for one completed without ever being issued. But io_clean_op() calls ->cleanup only if REQ_F_NEED_CLEANUP is set, and for uring_cmd that happens only where the vec has to grow, so a command reusing a large enough cached vec never sets it. io_rw_alloc_async() and io_msg_alloc_async() flag an inherited vec for exactly this reason; io_uring_cmd_prep() does not. Flag an inherited vec in io_uring_cmd_prep(), and free the vec when the cache put fails, as io_req_rw_cleanup() does. The leak is invisible under KASAN, where io_alloc_cache_vec_kasan() frees the vec unconditionally.

There are packages installed that are affected by a vulnerability referenced in the following CVE:

  - In the Linux kernel, the following vulnerability has been resolved: io_uring/cmd: fix iovec leak when the
    async cmd is not recycled An io_async_cmd carries an iovec array in ->vec.iovec, allocated when the vec
    has to grow and kept across recycling through ctx->cmd_cache. On two paths nothing frees it and
    io_clean_op()'s kfree(req->async_data) drops the io_async_cmd without it. io_req_uring_cleanup() clears
    the async data flags only when io_alloc_cache_put() succeeds, and the cache holds IO_ALLOC_CACHE_MAX ==
    128 entries, so once it is full the put fails and the vec is left behind. An NVMe passthrough workload
    gets there without doing anything unusual: nvme_uring_cmd_io() returns -EIOCBQUEUED, so the io_async_cmd
    stays attached for the lifetime of the command and the live object count tracks the queue depth. Above 128
    the puts start failing. ->cleanup is the last chance to free an inherited vec, since
    io_req_uring_cleanup() returns early for an io-wq issued command and is not called at all for one
    completed without ever being issued. But io_clean_op() calls ->cleanup only if REQ_F_NEED_CLEANUP is set,
    and for uring_cmd that happens only where the vec has to grow, so a command reusing a large enough cached
    vec never sets it. io_rw_alloc_async() and io_msg_alloc_async() flag an inherited vec for exactly this
    reason; io_uring_cmd_prep() does not. Flag an inherited vec in io_uring_cmd_prep(), and free the vec when
    the cache put fails, as io_req_rw_cleanup() does. The leak is invisible under KASAN, where
    io_alloc_cache_vec_kasan() frees the vec unconditionally. (CVE-2026-80811)

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - io_uring/cmd: fix iovec leak when the async cmd is not recycled An io_async_cmd carries an iovec array in
    ->vec.iovec, allocated when the vec has to grow and kept across recycling through ctx->cmd_cache. On two     paths nothing frees it and io_clean_op()'s kfree(req->async_data) drops the io_async_cmd without it.
    io_req_uring_cleanup() clears the async data flags only when io_alloc_cache_put() succeeds, and the cache     holds IO_ALLOC_CACHE_MAX == 128 entries, so once it is full the put fails and the vec is left behind. An     NVMe passthrough workload gets there without doing anything unusual: nvme_uring_cmd_io() returns
    -EIOCBQUEUED, so the io_async_cmd stays attached for the lifetime of the command and the live object count     tracks the queue depth. Above 128 the puts start failing. ->cleanup is the last chance to free an     inherited vec, since io_req_uring_cleanup() returns early for an io-wq issued command and is not called at     all for one completed without ever being issued. But io_clean_op() calls ->cleanup only if     REQ_F_NEED_CLEANUP is set, and for uring_cmd that happens only where the vec has to grow, so a command     reusing a large enough cached vec never sets it. io_rw_alloc_async() and io_msg_alloc_async() flag an     inherited vec for exactly this reason; io_uring_cmd_prep() does not. Flag an inherited vec in     io_uring_cmd_prep(), and free the vec when the cache put fails, as io_req_rw_cleanup() does. The leak is     invisible under KASAN, where io_alloc_cache_vec_kasan() frees the vec unconditionally. (CVE-2026-80811)

Note that Nessus relies on the presence of the package as reported by the vendor.

ID	Name	Product	Family	Type	Severity
471549	Google: sys-kernel/cchost-kernel-6_18, sys-kernel/csql-kernel-6_18, sys-kernel/lakitu-kernel-6_18, sys-kernel/lakitu-nc-kernel-6_18: security update to 20098.0.0	Tenable Cloud Security	Google COS Security Checks	Local	medium
471549	Google: sys-kernel/cchost-kernel-6_18, sys-kernel/csql-kernel-6_18, sys-kernel/lakitu-kernel-6_18, sys-kernel/lakitu-nc-kernel-6_18: security update to 20098.0.0	Tenable Self-Hosted Container Security	Google COS Security Checks	Local	medium
470632	Google: sys-kernel/cchost-kernel-6_18, sys-kernel/csql-kernel-6_18, sys-kernel/lakitu-kernel-6_18, sys-kernel/lakitu-nc-kernel-6_18: security update to 19999.44.28	Tenable Cloud Security	Google COS Security Checks	Local	medium
470632	Google: sys-kernel/cchost-kernel-6_18, sys-kernel/csql-kernel-6_18, sys-kernel/lakitu-kernel-6_18, sys-kernel/lakitu-nc-kernel-6_18: security update to 19999.44.28	Tenable Self-Hosted Container Security	Google COS Security Checks	Local	medium
351016	Amazon Linux 2023 : bpftool6.18, kernel6.18, kernel6.18-devel (ALAS2023-2026-3139)	Nessus	Amazon Linux Local Security Checks	Local	critical
343476	Linux Distros Unpatched Vulnerability : CVE-2026-80811	Nessus	Misc.	Local	high

Detections

Analytics

CVE-2026-80811

high

Tenable Plugins

medium

medium

medium

medium

critical

high