CVE-2026-0809 - Vulnerability Details - OpenCVE

Use of a custom token encoding algorithm in Streamsoft Prestiż software allows the value of the KSeF (Krajowy System e-Faktur) token to be guessed after analyzing how tokens with know values are encoded.

This issue was fixed in version 20.0.380.92.

Attack Vector Network

Attack Complexity Low

Privileges Required None

Attack Requirements Present

User Interaction None

Vulnerable System Confidentiality Impact Low

Vulnerable System Integrity Impact None

Vulnerable System Availability Impact None

Subsequent System Confidentiality Impact None

Subsequent System Integrity Impact None

Subsequent System Availability Impact None

No CVSS v3.1

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Exploitation none

Automatable yes

Technical Impact partial

No data.

No data.

No data.

No data.

Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References

Link	Providers
https://cert.pl/posts/2026/03/CVE-2026-0809
https://www.streamsoft.pl/streamsoft-prestiz/

History

Thu, 12 Mar 2026 14:15:00 +0000

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Thu, 12 Mar 2026 13:15:00 +0000

Type	Values Removed	Values Added
Description		Use of a custom token encoding algorithm in Streamsoft Prestiż software allows the value of the KSeF (Krajowy System e-Faktur) token to be guessed after analyzing how tokens with know values are encoded. This issue was fixed in version 20.0.380.92.
Title		Weak KSeF token encoding in Streamsoft Prestiż
Weaknesses		CWE-261
References		https://cert.pl/posts/2026/03/CVE-2026-0809 https://www.streamsoft.pl/streamsoft-prestiz/
Metrics		cvssV4_0 `{'score': 6.3, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N'}`

Projects

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MITRE

Status: PUBLISHED

Assigner: CERT-PL

Published: 2026-03-12T13:02:24.795Z

Updated: 2026-03-12T14:04:53.073Z

Reserved: 2026-01-09T14:56:38.137Z

Link: CVE-2026-0809

Vulnrichment

Updated: 2026-03-12T14:04:22.959Z

NVD

Status : Received

Published: 2026-03-12T13:16:00.723

Modified: 2026-03-12T13:16:00.723

Link: CVE-2026-0809

Redhat

No data.

OpenCVE Enrichment

No data.

Weaknesses

CWE-261

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