Thales Sentinel Keys Server prior 1.3.8.0 buffer overflow

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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9.6$0-$5k1.17-

Summaryinfo

A vulnerability, which was classified as very critical, was found in Thales Sentinel Keys Server. Affected is an unknown function. Executing a manipulation can lead to buffer overflow. This vulnerability is registered as CVE-2026-78403. It is possible to launch the attack remotely. No exploit is available. You should upgrade the affected component.

Detailsinfo

A vulnerability has been found in Thales Sentinel Keys Server and classified as very critical. This vulnerability affects some unknown functionality. The manipulation with an unknown input leads to a buffer overflow vulnerability. The CWE definition for the vulnerability is CWE-120. The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer, leading to a buffer overflow. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

Stack-based buffer overflow and missing authorization vulnerability in Thales Sentinel Keys Server on Windows allows Overflow Buffers. Sentinel Keys Server does not check the length of the first field in the HTTP request. An attacker may craft an HTTP request and send it to Sentinel Keys Server. It may lead to remote code execution as NT AUTHORITY\SYSTEM. This issue affects Sentinel Keys Server: versions lower than 1.3.8.0.

The advisory is shared for download at supportportal.thalesgroup.com. This vulnerability was named CVE-2026-78403 since 08/24/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. There are neither technical details nor an exploit publicly available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 10/30/2026).

Upgrading to version 1.3.8.0 eliminates this vulnerability.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Vendor

Name

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 9.9
VulDB Meta Temp Score: 9.6

VulDB Base Score: 10.0
VulDB Temp Score: 9.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 9.8
CNA Vector (THA-PSIRT): 🔒

CVSSv2info

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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Buffer overflow
CWE: CWE-120 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Sentinel Keys Server 1.3.8.0

Timelineinfo

08/24/2026 CVE reserved
10/30/2026 +67 days Advisory disclosed
10/30/2026 +0 days VulDB entry created
10/30/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: supportportal.thalesgroup.com
Status: Confirmed

CNA: THA-PSIRT
CVE: CVE-2026-78403 (🔒)

GCVE (CVE): GCVE-0-2026-78403
GCVE (VulDB): GCVE-100-429340

Entryinfo

Created: 10/30/2026 20:25
Changes: 10/30/2026 20:25 (73)
Complete: 🔍
Cache ID: 216::103

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