Is CVE-2026-88830 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-88830 being exploited in the wild.

How severe is CVE-2026-88830?

High severity, with a CVSS score of 7.5, published 23 September 2026.

Which products and versions are affected?

Busybox affected versions not specified.

Is there a fix for CVE-2026-88830?

No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

How is CVE-2026-88830 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2026-88830?

Check whether you run Busybox at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-88830: BusyBox TLS heap buffer overflow in Montgomery reduction

CVE-2026-88830 · Severity: high · CVSS 7.5 · Published 2026-09-23

BusyBox includes a lightweight TLS server utility that contains a buffer allocation bug in cryptographic processing. An unauthenticated attacker can crash the TLS server by sending a crafted TLS handshake message, causing denial of service. The vulnerability is limited to BusyBox's test ssl_server applet and does not affect standard BusyBox installations shipped in distributions.

Technologies: Busybox. Vendors: Busybox.

Quick answers

Is CVE-2026-88830 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-88830 being exploited in the wild.
How severe is CVE-2026-88830?: High severity, with a CVSS score of 7.5, published 23 September 2026.
Which products and versions are affected?: Busybox affected versions not specified.
Is there a fix for CVE-2026-88830?: No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-88830 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-88830?: Check whether you run Busybox at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

A unit confusion in TLS Montgomery reduction buffer allocation (CWE-131) causes a pre-authentication heap buffer overflow when processing a ClientKeyExchange message. The attack is unauthenticated and network-accessible with no user interaction required, resulting in crash or potential code execution. Red Hat states that system mitigations (ASLR, PIE, RELRO, SELinux) prevent practical exploitation.

Affected products

BusyBox BusyBox affected versions not specified

Timeline

2026-09-23: disclosed

References

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