What is CVE-2026-31402?

CVE-2026-31402 is a critical-severity vulnerability in Linux, classified under Out-of-bounds Write. CVSS score: 9.8/10. Published 2026-04-03.

How severe is CVE-2026-31402?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Is CVE-2026-31402 known to be exploited?

1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Buffer overflow in Linux

CVE-2026-31402

In the Linux kernel, the following vulnerability has been resolved: nfsd: fix heap overflow in NFSv4.0 LOCK replay cache The NFSv4.0 replay cache uses a fixed 112-byte inline buffer (rp_ibuf[NFSD4_REPLAY_ISIZE]) to store encoded operatio…

Vulnerability class: Buffer Overflow

EPSS: 0.001 (34.7th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Linux — versions 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, 2.6.12, 0
Linux Linux_kernel — versions 2.6.12, 7.0

Weakness classification (CWE)

CWE-787 — Out-of-bounds Write

Public proof-of-concept exploits

0xBlackash/CVE-2026-31402

References

416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)

Frequently asked questions

What is CVE-2026-31402?: CVE-2026-31402 is a critical-severity vulnerability in Linux, classified under Out-of-bounds Write. CVSS score: 9.8/10. Published 2026-04-03.
How severe is CVE-2026-31402?: Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2026-31402 known to be exploited?: 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.