What is CVE-2026-63886?

CVE-2026-63886 is a critical-severity vulnerability in Linux. CVSS score: 9.8/10. Published 2026-07-19.

How severe is CVE-2026-63886?

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

Vulnerability in Linux

CVE-2026-63886

In the Linux kernel, the following vulnerability has been resolved: scsi: target: iscsi: Validate CHAP_R length before base64 decode chap_server_compute_hash() allocates client_digest as kzalloc(chap->digest_size) and then, for BASE64-en…

EPSS: 0.002 (10.7th 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 1e5733883421495908f3b90d9d807663038b4136, 6.0, 0

References

416baaa9-dc9f-4396-8d5f-8c081fb06d67
416baaa9-dc9f-4396-8d5f-8c081fb06d67
416baaa9-dc9f-4396-8d5f-8c081fb06d67
416baaa9-dc9f-4396-8d5f-8c081fb06d67
416baaa9-dc9f-4396-8d5f-8c081fb06d67
416baaa9-dc9f-4396-8d5f-8c081fb06d67

Frequently asked questions

What is CVE-2026-63886?: CVE-2026-63886 is a critical-severity vulnerability in Linux. CVSS score: 9.8/10. Published 2026-07-19.
How severe is CVE-2026-63886?: Critical severity. CVSS v3 base score is 9.8 out of 10.