Vulnerability · Published Sep 23, 2026 · Assigned by redhat
CVE-2026-88830Busybox: busybox: tls montgomery reduction allocates bytes instead of digits, causing a pre-auth heap buffer overflow
High 7.5
In plain English
A high-severity security flaw in Red Hat Hardened Images from Red Hat. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 29% of all known vulnerabilities).
Severity (CVSS 3.1)7.5High
Exploit odds (30 days)0.4%top 71.1% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
A unit confusion in BusyBox TLS Montgomery reduction buffer allocation causes a pre-authentication heap buffer overflow when processing a crafted ClientKeyExchange message.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | busybox | no fix listed | DEBIAN-CVE-2026-88830 |
| Debian:13 | busybox | no fix listed | DEBIAN-CVE-2026-88830 |
| Debian:14 | busybox | no fix listed | DEBIAN-CVE-2026-88830 |
| Ubuntu:22.04:LTS | busybox | no fix listed | UBUNTU-CVE-2026-88830 |
| Ubuntu:24.04:LTS | busybox | no fix listed | UBUNTU-CVE-2026-88830 |
| Ubuntu:26.04:LTS | busybox | no fix listed | UBUNTU-CVE-2026-88830 |
| Ubuntu:26.10 | busybox | no fix listed | UBUNTU-CVE-2026-88830 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Red Hat | Red Hat Hardened Images | see references |
Weakness: CWE-131 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
References
- https://access.redhat.com/security/cve/CVE-2026-88830 vdb-entry, x_refsource_REDHAT
- RHBZ#2531344 issue-tracking, x_refsource_REDHAT