Stack-based buffer overflow in SafeNet Authentication Client SIS token engine

published 2026-11-05 3 d ago modified 2026-11-06 2 d ago also EUVD-2026-117636

cvss: 6.8; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.3%; EPSS 0.3% chance of exploitation in 30 days, percentile 16%
public exploits: 0; none known

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).

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-94395 updated 2026-11-06 cvss 6.8

SafeNet Authentication Client: SafeNet Authentication Client: arbitrary code execution via malicious smart card

Red Hat All currently supported Red Hat products
not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: total
Assessed: 3 d ago (2026-11-05)

Exploit prediction

0.25% chance of exploitation in the next 30 days, higher than 16% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	4.0	7.0	CVSS:4.0/AV:P/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
CISA ADP	3.1	6.8	CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CNA	4.0	7.0	CVSS:4.0/AV:P/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CNA	3.1	6.8	CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected products

Thalesgroup Safenet Authentication Client SIS token engine

Classification

Weakness

CWE-1284 Improper Validation of Specified Quantity in Input
CWE-787 Out-of-bounds Write
CWE-121 Stack-based Buffer Overflow

References

supportportal.thalesgroup.com /csm?id=kb_article_view&sys_kb_id=7786064a2b905350cdc1f87df291bf92&sysparm_article=KB0031250
vendor-advisory

Sources

CVE List CVE-2026-94395
NVD CVE-2026-94395

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary