CVE-2026-88830
📛 CVE Title
Busybox: busybox: tls montgomery reduction allocates bytes instead of digits, causing a pre-auth heap buffer overflow
Description
A unit confusion in BusyBox TLS Montgomery reduction buffer allocation causes a pre-authentication heap buffer overflow when processing a crafted ClientKeyExchange message.
Overview
- State
- PUBLISHED
- Assigner (CNA)
- redhat
- CVSS severity
- HIGH
- CVSS score
- 7.5 / 10
- CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H- Effective score
- 7.5 / 10 HIGH source: CNA overview
- CWE(s)
-
CWE-131 - Reserved
- 2026-09-10
- Published
- 2026-09-23 17:04 UTC
- Last updated
- 2026-09-23 19:44 UTC
- Source
- https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/88xxx/CVE-2026-88830.json
- Linked Threat
- CVE-2026-88830 — Busybox: busybox: tls montgomery reduction allocates bytes instead of digits, causing a pre-auth heap buffer overflow
NVD triage scoring NVD CVE 2.0
Layer NVD adds on top of the CNA's CVE record — published / last-modified timestamps, exploitability / impact subscores, and the FIRST.org EPSS probability that this CVE will be exploited in the wild in the next 30 days.
- NVD published
- 2026-09-23 17:17:18 UTC
- NVD last modified
- 2026-09-23 20:17:20 UTC
- NVD CVSS v3.1
- 7.5 / 10 HIGH source: secalert@redhat.com
- NVD CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H- Exploitability subscore
- 3.9 / 10
- Impact subscore
- 3.6 / 10
NVD / KEV / EPSS data refreshed 2026-09-24 04:31 UTC. Re-run the 🛰 Backfill from NVD button above to refresh.
European Union Vulnerability Database ENISA EUVD
ENISA's official EU repository for curated vulnerability intelligence. Carries a separate identifier (EUVD-YYYY-NNNN) and frequently exposes an earlier-published description + CVSS than NVD does.
- EUVD ID
-
EUVD-2026-85425 - Assigner
- redhat
- Published
- Sep 23, 2026, 5:04:57 PM
- Updated
- Sep 23, 2026, 7:44:18 PM
- EUVD base score (CVSS 3.1)
-
7.5 / 10
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - EUVD-reported EPSS
- 0.0000
- Aliases
-
GHSA-mv57-fr8w-22gj
ENISA 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 products (1)
| Vendor | Product | Versions | Platforms |
|---|---|---|---|
| Red Hat | Red Hat Hardened Images | — | — |
Vendor references (2)
References embedded in the original CVE record by the assigning CNA.
- https://access.redhat.com/security/cve/CVE-2026-88830 vdb-entryx_refsource_REDHAT
- RHBZ#2531344 issue-trackingx_refsource_REDHAT
Web references (0)
DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.
No web references attached yet.
NVD-tagged references (2)
Reference list NVD curates from the CNA record, vendor advisories, and third-party reports. The tag chips below are NVD's analyst-assigned categories.
- https://access.redhat.com/security/cve/CVE-2026-88830 secalert@redhat.com
- https://bugzilla.redhat.com/show_bug.cgi?id=2531344 secalert@redhat.com
Remediations (10)
Remediations are stored against the linked Threat row; the list below is deduplicated across both pages.
-
web:access.redhat.com
Overall, you have the following options: Upgrade to a supported product version that includes a fix for this vulnerability (recommended). Apply a mitigation (if one exists). Customers with the Technical Account Manager (TAM) RHEL Security Select Add-on can review this CVE directly with their TAM.
2026-09-24 11:10 UTC -
web:access.redhat.com
Products & tools Red Hat Documentation Find answers, get guidance, and learn how to use Red Hat products. Red Hat Ecosystem Catalog Find hardware, software, and cloud providers―and download container images―certified to perform with Red Hat technologies.
2026-09-24 11:10 UTC -
web:msrc.microsoft.com
The Microsoft Security Response Center (MSRC) investigates all reports of security vulnerabilities affecting Microsoft products and services, and provides the information here as part of the ongoing effort to help you manage security risks and help keep your systems protected.
2026-09-24 11:10 UTC -
web:nvd.nist.gov
Description A flaw was found in Keycloak. An authenticated user can bypass configured WebAuthn policies during credential registration by manipulating client-side JavaScript. This occurs because the server-side processAction () fails to validate that the newly created credential's parameters, such as public key algorithms, match the realm's configured WebAuthn policies. This could lead to the ...
2026-09-24 11:10 UTC -
web:sec.cloudapps.cisco.com
On September 16, 2026 , the Cisco Product Security Incident Response Team (PSIRT) published the advisories that are listed in the following tables. To remediate these vulnerabilities, Cisco strongly recommends that customers upgrade to the fixed software that is indicated in the advisories. For more information about changes in Cisco PSIRT vulnerability disclosure, see Strengthening the ...
2026-09-24 11:10 UTC -
web:senserva.com
Every Microsoft security patch (KB) and the CVEs it fixes, with severity, CVSS, and CISA KEV status. Cross-linked to the CVE reference.
2026-09-24 11:10 UTC -
web:support.microsoft.com
Note To apply this security update, you must have the release version of Excel 2016 installed on the computer.
2026-09-24 11:10 UTC -
web:support.microsoft.com
This out-of-band (OOB) update for Windows 11, version 25H2 and Windows 11, version 24H2 (KB5121768) is cumulative. It includes all improvements from previous security and non-security updates, along with an additional fix . Improvements This OOB update includes the following improvement: [System Performance] This update addresses an issue affecting a limited number of devices with an Intel ...
2026-09-24 11:10 UTC -
web:www.cisecurity.org
<p>Multiple vulnerabilities have been discovered in Microsoft products, the most severe of which could allow for remote code execution. Successful exploitation of the most severe of these vulnerabilities could result in an attacker gaining the same privileges as the logged-on user. Depending on the privileges associated with the user, an attacker could then install programs; view, change, or ...
2026-09-24 11:10 UTC -
web:zecurit.com
Get the complete breakdown of Microsoft's September 2026 Patch Tuesday. We analyze the latest security updates and all critical CVEs .
2026-09-24 11:10 UTC
AI Forensic Analysis
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Raw JSON
The full cvelistV5 record. Download as CVE-2026-88830.json.
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