io_uring/fdinfo: fix OOB read in SQE_MIXED wrap check
Summary
| CVE | CVE-2026-31484 |
|---|---|
| State | PUBLISHED |
| Assigner | Linux |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-04-22 14:16:45 UTC |
| Updated | 2026-04-28 13:39:16 UTC |
| Description | In the Linux kernel, the following vulnerability has been resolved: io_uring/fdinfo: fix OOB read in SQE_MIXED wrap check __io_uring_show_fdinfo() iterates over pending SQEs and, for 128-byte SQEs on an IORING_SETUP_SQE_MIXED ring, needs to detect when the second half of the SQE would be past the end of the sq_sqes array. The current check tests (++sq_head & sq_mask) == 0, but sq_head is only incremented when a 128-byte SQE is encountered, not on every iteration. The actual array index is sq_idx = (i + sq_head) & sq_mask, which can be sq_mask (the last slot) while the wrap check passes. Fix by checking sq_idx directly. Keep the sq_head increment so the loop still skips the second half of the 128-byte SQE on the next iteration. |
Risk And Classification
Primary CVSS: v3.1 7.1 HIGH from 416baaa9-dc9f-4396-8d5f-8c081fb06d67
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
EPSS: 0.000180000 probability, percentile 0.049720000 (date 2026-04-27)
Problem Types: CWE-125
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | Secondary | 7.1 | HIGH | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H |
| 3.1 | CNA | DECLARED | 7.1 | HIGH | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H |
CVSS v3.1 Breakdown
Attack Vector
LocalAttack Complexity
LowPrivileges Required
LowUser Interaction
NoneScope
UnchangedConfidentiality
HighIntegrity
NoneAvailability
HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
NVD Known Affected Configurations (CPE 2.3)
| Type | Vendor | Product | Version | Update | Edition | Language |
|---|---|---|---|---|---|---|
| Operating System | Linux | Linux Kernel | All | All | All | All |
| Operating System | Linux | Linux Kernel | 6.19 | - | All | All |
| Operating System | Linux | Linux Kernel | 7.0 | rc1 | All | All |
| Operating System | Linux | Linux Kernel | 7.0 | rc2 | All | All |
| Operating System | Linux | Linux Kernel | 7.0 | rc3 | All | All |
| Operating System | Linux | Linux Kernel | 7.0 | rc4 | All | All |
| Operating System | Linux | Linux Kernel | 7.0 | rc5 | All | All |
| Operating System | Linux | Linux Kernel | 7.0 | rc6 | All | All |
| Operating System | Linux | Linux Kernel | 7.0 | rc7 | All | All |
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Linux | Linux | affected 1cba30bf9fdd6c982708f3587f609a30c370d889 ba21ab247a5be5382da7464b95afbe5f0e9aa503 git | Not specified |
| CNA | Linux | Linux | affected 1cba30bf9fdd6c982708f3587f609a30c370d889 5170efd9c344c68a8075dcb8ed38d3f8a60e7ed4 git | Not specified |
| CNA | Linux | Linux | affected 6.19 | Not specified |
| CNA | Linux | Linux | unaffected 6.19 semver | Not specified |
| CNA | Linux | Linux | unaffected 6.19.11 6.19.* semver | Not specified |
| CNA | Linux | Linux | unaffected 7.0 * original_commit_for_fix | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| git.kernel.org/stable/c/ba21ab247a5be5382da7464b95afbe5f0e9aa503 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | Patch |
| git.kernel.org/stable/c/5170efd9c344c68a8075dcb8ed38d3f8a60e7ed4 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | Patch |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.