What is CVE-2026-88839?

CVE-2026-88839 is a medium-severity vulnerability in Red Hat Hardened Images, classified under Out-of-bounds Write. CVSS score: 6.7/10. Published 2026-09-23.

How severe is CVE-2026-88839?

Medium severity. CVSS v3 base score is 6.7 out of 10.

Buffer overflow in Red Hat Hardened Images

CVE-2026-88839

BusyBox passwd/group tokenize() references a stale endpoint pointer after trimming, causing an out-of-bounds write of heap pointers.

Vulnerability class: Buffer Overflow

Published 2026-09-23 · last modified 2026-09-25.

CVSS v3 metric

CVSS v3 base score 6.7 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.001 (2.1th percentile), scored 2026-11-04.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 2nd percentile — 2.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.001 · newest: 0.001 · change: +0.000

Affected products

Red Hat Hardened Images

Weakness classification (CWE)

CWE-787 — Out-of-bounds Write

References

access.redhat.com/security/cve/CVE-2026-88839 (vdb-entry)
bugzilla.redhat.com/show_bug.cgi (issue-tracking)
access.redhat.com/errata/RHSA-2026:72111 (vendor-advisory)

Frequently asked questions

What is CVE-2026-88839?: CVE-2026-88839 is a medium-severity vulnerability in Red Hat Hardened Images, classified under Out-of-bounds Write. CVSS score: 6.7/10. Published 2026-09-23.
How severe is CVE-2026-88839?: Medium severity. CVSS v3 base score is 6.7 out of 10.