CVE-2026-94395Thalesgroup Safenet Authentication Client SIS token engine stack-based buffer overflow
CVE-2026-94395 is a stack-based buffer overflow in Thalesgroup Safenet Authentication Client SIS token engine, rated high (7.0 on CVSS 4.0).
Why this priority: High severity, with no exploitation signal yet.
Published · Updated · NVD status: Awaiting Analysis
What it is
A buffer on the stack overflows, which can overwrite return addresses and hand an attacker control of execution. Code writes past the end of a buffer, corrupting memory in ways an attacker can often turn into code execution.
How it is reached
An attacker can exploit it with physical access to the device, without an account, and nobody has to click anything.
What an attacker gains
A successful attack can read the data it protects, change data or behaviour and take it offline. In practice, this kind of flaw lets an attacker crash the process, read memory, or in the worst case run code.
Is it being exploited?
There is no public report of exploitation yet. EPSS estimates a 0.25% chance of exploitation activity in the next 30 days, higher than 16% of scored CVEs.
What to do
- No fixed version is listed yet. Find every place Thalesgroup Safenet Authentication Client SIS token engine runs, watch the references for a fix, and plan a replacement if it is no longer supported.
Description from NVD
A stack-based buffer overflow in Thales SafeNet Authentication Client (SAC) SIS token engine processing can be triggered by a malicious physical or software-emulated smart card. The issue can occur before authentication or PIN entry and may cause a denial of service or potentially arbitrary code execution with the privileges of the affected process. Affected releases start with SAC 10.8 R7 and include SAC 10.9 R3 GA (build 10.9.7449).
What this means for your architecture.
A CVE names a product. Whether it matters depends on where that product sits in your systems: what reaches it, which trust boundary it guards and what it can reach once compromised. Veriom maps your components, their relationships and your trust boundaries from your code, cloud and delivery evidence, so you can see where a component like this sits. The radar itself does not look at your systems.
Components it touches
- Native code: operating systems, browsers and firmware. The flaw sits wherever native code reads untrusted data.
- Network appliances and media or file parsers. The flaw sits wherever native code reads untrusted data.
- Interfaces that accept external input. The flaw sits at the input boundary of the affected component.
Trust boundaries in play
- Host boundary. The attacker needs a foothold on the machine first; the flaw turns a small foothold into a bigger one.
- Wherever native code reads untrusted data. An attacker who crosses it can crash the process, read memory, or in the worst case run code.
- At the input boundary of the affected component. An attacker who crosses it can drive the component into behaviour its authors did not intend.
Questions to answer about your own systems
- Where does Thalesgroup Safenet Authentication Client SIS token engine run in your systems, and at which version?
- Which of those devices sit where outsiders can touch them?
- What can it reach once compromised: which data stores, secrets and services?
Sources
- CVE records and CVSS scores from the NVD CVE API. This product uses the NVD API but is not endorsed or certified by the NVD.
- Exploitation status from CISA’s Known Exploited Vulnerabilities catalog.
- Exploit likelihood from FIRST’s Exploit Prediction Scoring System (EPSS), refreshed daily.
- Explanations are written by Veriom from fixed templates over each record’s data, not by a person reviewing each CVE. Descriptions are quoted from the records as published.