Vulnerability record · CVE-2026-64522 · published 25 July 2026
CVE-2026-64522: In the Linux kernel, the following vulnerability has been resolved: net/mlx5e: Fix eswitch mode block underfl…
In the Linux kernel, the following vulnerability has been resolved: net/mlx5e: Fix eswitch mode block underflow on IPsec acquire SA mlx5e_xfrm_add_state() handles acquire-flow temporary SAs by allocating software state and skipping hardware offload setup. That path jumps to the common success label before taking the eswitch mode block. After tunnel-mode validation was moved earlier, the common success label unconditionally calls mlx5_eswitch_unblock_mode(). For acquire SAs, this decrements esw->offloads.num_block_mode without a matching increment. Return directly after installing the acquire SA offload handle, so only the paths that successfully called mlx5_eswitch_block_mode() call the matching unblock.
Description
In the Linux kernel, the following vulnerability has been resolved: net/mlx5e: Fix eswitch mode block underflow on IPsec acquire SA mlx5e_xfrm_add_state() handles acquire-flow temporary SAs by allocating software state and skipping hardware offload setup. That path jumps to the common success label before taking the eswitch mode block. After tunnel-mode validation was moved earlier, the common success label unconditionally calls mlx5_eswitch_unblock_mode(). For acquire SAs, this decrements esw->offloads.num_block_mode without a matching increment. Return directly after installing the acquire SA offload handle, so only the paths that successfully called mlx5_eswitch_block_mode() call the matching unblock.
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
References
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Source: NIST National Vulnerability Database (record CVE-2026-64522), CISA KEV, FIRST EPSS (scores of 2026-09-27). This page is refreshed as NVD updates the record.
