CVE-2026-21863

Exploitation

Assessed, none found. CISA's assessment recorded neither public exploit code nor evidence of exploitation when it was made.

SSVC decision

• ExploitationnoneCISA recorded no public exploit code and no evidence of exploitation.
• AutomatableyesAn attacker can reliably automate reconnaissance through exploitation, so this scales.
• Technical ImpactpartialSuccessful exploitation gives limited control of the vulnerable component.

CISA publishes the decision points, not a final SSVC decision. The decision also depends on mission and well-being impact, which is a property of your deployment rather than of the vulnerability.

EPSS probability

0.84% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 57.6% of scored records. A rank, not a probability.

NVD base score

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

NVD CVSS vector

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

NVD analysis status

Modified. NVD last modified this record on 2026-07-15.

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

2026-02-23 19:41Z8 MO AGO

Last updated

2026-07-15 01:19Z3 MO AGO

Reserved

2026-01-05

Assigning CNA

GitHub_M

Record state

PUBLISHED

Severity

High (CVSS 7.5)

CNA CVSS vector

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

Weaknesses

• CWE-125Out-of-bounds ReadBase

Data version

5.2

Document digest

87c1ee2b83cb149fb57a56ac23183f7b0621fb508bf8151c20663c591ccc42b4

• github.comhttps://github.com/valkey-io/valkey/security/advisories/GHSA-c677-q3wr-gggqx_refsource_CONFIRM
• access.redhat.comhttps://access.redhat.com/security/cve/CVE-2026-21863vdb-entryx_refsource_REDHAT
• bugzilla.redhat.comRHBZ#2442026https://bugzilla.redhat.com/show_bug.cgi?id=2442026issue-trackingx_refsource_REDHAT
• security.access.redhat.comhttps://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-21863.jsonx_sadp-csaf-vex
• access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:5445vendor-advisoryx_refsource_REDHAT
• access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:3443vendor-advisoryx_refsource_REDHAT
• access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:3507vendor-advisoryx_refsource_REDHAT
• access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:8753vendor-advisoryx_refsource_REDHAT