CVE-2021-25217

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

6.11% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 93.3% of scored records. A rank, not a probability.

NVD base score

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

NVD CVSS vector

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

NVD analysis status

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

Red Hat severity

Important. Red Hat's rating for its own products, not a CVSS rating.

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

2021-05-26 22:10Z5 YR AGO

Last updated

2024-09-16 22:08Z2 YR AGO

Reserved

2021-01-15

Assigning CNA

isc

Record state

PUBLISHED

Severity

High (CVSS 7.4)

CNA CVSS vector

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

Weaknesses

• CWE-119Improper Restriction of Operations within the Bounds of a Memory BufferClass

Data version

5.1

Document digest

6bf69cced258179f7f14289889125768149c3d2636c4c0cb199e252f664b7591

• kb.isc.orghttps://kb.isc.org/docs/cve-2021-25217
• www.openwall.com[oss-security] 20210526 ISC has disclosed a vulnerability in ISC DHCP (CVE-2021-25217)http://www.openwall.com/lists/oss-security/2021/05/26/6mailing-list
• lists.fedoraproject.orgFEDORA-2021-08cdb4dc34https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/Z2LB42JWIV4M4WDNXX5VGIP26FEYWKIF/vendor-advisory
• lists.debian.org[debian-lts-announce] 20210603 [SECURITY] [DLA 2674-1] isc-dhcp security updatehttps://lists.debian.org/debian-lts-announce/2021/06/msg00002.htmlmailing-list
• lists.fedoraproject.orgFEDORA-2021-8ca8263bdehttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5QI4DYC7J4BGHEW3NH4XHMWTHYC36UK4/vendor-advisory
• cert-portal.siemens.comhttps://cert-portal.siemens.com/productcert/pdf/ssa-406691.pdf
• security.netapp.comhttps://security.netapp.com/advisory/ntap-20220325-0011/
• cert-portal.siemens.comhttps://cert-portal.siemens.com/productcert/pdf/ssa-637483.pdf
• security.gentoo.orgGLSA-202305-22https://security.gentoo.org/glsa/202305-22vendor-advisory