CVE-2021-28698

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

0.34% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 28.0% 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

2021-08-27 18:32Z5 YR AGO

Last updated

2024-08-03 21:47Z2 YR AGO

Reserved

2021-03-18

Assigning CNA

XEN

Record state

PUBLISHED

Severity

Not rated by the issuing CNA

CNA CVSS vector

Not published by the issuing CNA

Weaknesses

• CWE-835Loop with Unreachable Exit Condition ('Infinite Loop')Base

Data version

5.1

Document digest

0d218b57910eb33529ad3a297fd11baab9073d186956b3ff7d01ac489c8a7bb7

• xenbits.xenproject.orghttps://xenbits.xenproject.org/xsa/advisory-380.txtx_refsource_MISC
• www.openwall.com[oss-security] 20210901 Xen Security Advisory 380 v3 (CVE-2021-28698) - long running loops in grant table handlinghttp://www.openwall.com/lists/oss-security/2021/09/01/2mailing-listx_refsource_MLIST
• lists.fedoraproject.orgFEDORA-2021-4f129cc0c1https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/LPRVHW4J4ZCPPOHZEWP5MOJT7XDGFFPJ/vendor-advisoryx_refsource_FEDORA
• lists.fedoraproject.orgFEDORA-2021-d68ed12e46https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FZCNPSRPGFCQRYE2BI4D4Q4SCE56ANV2/vendor-advisoryx_refsource_FEDORA
• www.debian.orgDSA-4977https://www.debian.org/security/2021/dsa-4977vendor-advisoryx_refsource_DEBIAN
• lists.fedoraproject.orgFEDORA-2021-081f9bf5d2https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/2VQCFAPBNGBBAOMJZG6QBREOG5IIDZID/vendor-advisoryx_refsource_FEDORA
• security.gentoo.orgGLSA-202208-23https://security.gentoo.org/glsa/202208-23vendor-advisoryx_refsource_GENTOO