Vulnerability in Krajowa Izba Rozliczeniowa Szafir Sdk
CVE-2026-9058
For untrusted certificates that contain the "Authority Information Access - caIssuers URI" extension, Szafir SDK will automatically download the parent CA certificate from the specified URL and will import it to its trust store as a "nonqualified" certificate. In such a case, Szafir SDK returns a success status code of 0 ("Positively verified") upon successful cryptographic verification and a certificate status of "nonqualified". For other types of untrusted certificates, Szafir SDK returns a success status code of 0 ("Positively verified") upon successful cryptographic verification and a certificate status of "nondetermined". This may lead integrating applications to incorrectly treat the digital signature as valid despite an untrusted certificate chain. This flaw enables authentication bypass and user impersonation: (1) in use-cases other than qualified certificate authentication, or (2) if the qualified certificate authentication use-case is not correctly implemented by the integrating application. This issue was fixed in version 1.8.463.2.
Vulnerability class: Improper Certificate Validation
Published · last modified .
EPSS exploit prediction
EPSS: 0.004 (30.1th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 30th percentile — 30.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.004 · change: +0.001
Affected products
- Krajowa Izba Rozliczeniowa Szafir Sdk — versions 0
Weakness classification (CWE)
References
- cert.pl/posts/2026/05/CVE-2026-9058 (third-party-advisory)
- www.elektronicznypodpis.pl/ (product)