CVE-2021-28701

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

0.26% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 18.3% of scored records. A rank, not a probability.

NVD base score

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

NVD CVSS vector

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

2021-09-08 13:02Z5 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-362Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')Class

Data version

5.1

Document digest

e85234827db4e6025a49a493c81ead010298d2871ed31987cd46a8dfe925247e

• xenbits.xenproject.orghttps://xenbits.xenproject.org/xsa/advisory-384.txtx_refsource_MISC
• xenbits.xen.orghttp://xenbits.xen.org/xsa/advisory-384.htmlx_refsource_CONFIRM
• www.openwall.com[oss-security] 20210908 Xen Security Advisory 384 v3 (CVE-2021-28701) - Another race in XENMAPSPACE_grant_table handlinghttp://www.openwall.com/lists/oss-security/2021/09/08/2mailing-listx_refsource_MLIST
• lists.fedoraproject.orgFEDORA-2021-11577e5229https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/L4MI3MQAPGILCLXBGQWPZHGE3ALSO4ZU/vendor-advisoryx_refsource_FEDORA
• lists.fedoraproject.orgFEDORA-2021-fed53cbc7dhttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CEHZLIR5DFYYQBH55AERWHLO54OFU42C/vendor-advisoryx_refsource_FEDORA
• www.debian.orgDSA-4977https://www.debian.org/security/2021/dsa-4977vendor-advisoryx_refsource_DEBIAN
• lists.fedoraproject.orgFEDORA-2021-5a0c7bc619https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/3HEHUIUWSSMCQGQY3GWX4J2SZGYP5W2Z/vendor-advisoryx_refsource_FEDORA
• security.gentoo.orgGLSA-202208-23https://security.gentoo.org/glsa/202208-23vendor-advisoryx_refsource_GENTOO