CVE-2021-3308

Exploitation

Not assessed. CISA has not published an exploitation assessment for this record, and it is not in the KEV catalog. That is an absence of assessment, not a finding of no risk.

SSVC decision

Not assessed by CISA

EPSS probability

0.42% probability of exploitation activity in the next 30 days.

EPSS percentile

Ranks above 34.7% of scored records. A rank, not a probability.

NVD base score

5.5 (CVSS v3.x), scored by the NVD independently of the CNA.

NVD CVSS vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

NVD analysis status

Modified. NVD last modified this record on 2026-06-17.

Red Hat severity

No Red Hat rating. Red Hat rates the CVEs that affect its products.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

Published

2021-01-26 19:58Z5 YR AGO

Last updated

2024-08-03 16:53Z2 YR AGO

Reserved

2021-01-26

Assigning CNA

mitre

Record state

PUBLISHED

Severity

Not rated by the issuing CNA

CNA CVSS vector

Not published by the issuing CNA

Weaknesses

No CWE assigned

Data version

5.1

Document digest

7b17fc9ce3a5f2f74ea7f910e2c2a6214675314012d7fe72a95aa29496a1cd39

• xenbits.xen.orghttp://xenbits.xen.org/xsa/advisory-360.htmlx_refsource_MISC
• www.openwall.com[oss-security] 20210126 Xen Security Advisory 360 v2 (CVE-2021-3308) - IRQ vector leak on x86http://www.openwall.com/lists/oss-security/2021/01/26/4mailing-listx_refsource_MLIST
• lists.fedoraproject.orgFEDORA-2021-16c9c40d4dhttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/S5C42TMQYB6SDVT2MPFEWY65A6RSUVBN/vendor-advisoryx_refsource_FEDORA
• security.gentoo.orgGLSA-202107-30https://security.gentoo.org/glsa/202107-30vendor-advisoryx_refsource_GENTOO