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CVE-2026-0809 (GCVE-0-2026-0809)

Vulnerability from cvelistv5 – Published: 2026-03-12 13:02 – Updated: 2026-03-12 14:04
VLAI
Title
Weak KSeF token encoding in Streamsoft Prestiż
Summary
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.
Severity
6.3 (Medium)
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
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-12 14:04 UTC
CWE
  • CWE-261 - Weak Encoding for Password
Assigner
References
Impacted products
Vendor Product Version CPE status
Streamsoft Streamsoft Prestiż Affected: 12.2.363.17 , < 20.0.380.92 (custom)
guessed Create a notification for this product.
Credits
Kamil Dąbkowski
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.


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Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.