Buffer overflow in Linux

CVE-2026-23326

In the Linux kernel, the following vulnerability has been resolved: xsk: Fix fragment node deletion to prevent buffer leak After commit b692bf9a7543 ("xsk: Get rid of xdp_buff_xsk::xskb_list_node"), the list_node field is reused for both the xskb pool list and the buffer free list, this causes a buffer leak as described below. xp_free() checks if a buffer is already on the free list using list_empty(&xskb->list_node). When list_del() is used to remove a node from the xskb pool list, it doesn't reinitialize the node pointers. This means list_empty() will return false even after the node has been removed, causing xp_free() to incorrectly skip adding the buffer to the free list. Fix this by using list_del_init() instead of list_del() in all fragment handling paths, this ensures the list node is reinitialized after removal, allowing the list_empty() to work correctly.

Vulnerability class: Buffer Overflow

EPSS: 0.001 (2.9th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

Affected products

  • Linux — versions 560c974b7ccd95bb9ff20df77f6654283e45c9c6, fd5614763805d6f386bd07cc53558f88b1b1eb62, b692bf9a7543af7ad11a59d182a3757578f0ba53
  • Linux Linux_kernel — versions 6.13, 7.0

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-23326?
CVE-2026-23326 is a high-severity vulnerability in Linux, classified under Out-of-bounds Write. CVSS score: 7.8/10. Published 2026-03-25.
How severe is CVE-2026-23326?
High severity. CVSS v3 base score is 7.8 out of 10.