Paper/Archive/CVE-2026-9058

CVE-2026-9058

Krajowa Izba Rozliczeniowa Szafir SDK — Improper Certificate Verification in Szafir SDK

Description · from the CVE record

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.

Affected

ProductAffectedFixed inSource
Szafir SDK< 1.8.463.21.8.463.2CNA

Scores by source

CERT-PL (CNA)9.3CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
CISA ADPSSVCExploitation: none · Automatable: yes · Technical impact: total

References

writeupcert.pl/posts/2026/05/CVE-2026-9058refelektronicznypodpis.pl