Vulnerability · Published Jun 2, 2026 · Assigned by CERT-PL

CVE-2026-34906Server-Side Template Injection (SSTI) in Wirtualna Uczelnia

Critical 9.3

In plain English

A critical-severity security flaw in Wirtualna Uczelnia from Simple SA. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.6% (higher than 47% of all known vulnerabilities).

Severity (CVSS 4.0)9.3Critical

Exploit odds (30 days)0.6%top 53.4% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

Server-Side Template Injection (SSTI) in Wirtualna Uczelnia allows an unauthenticated attacker to perform Remote Code Execution (RCE). In the endpoint redirectToUrl and parameter redirectUrlParameter, insufficient input validation permits injection of arbitrary template expressions that are executed on the server. Successful exploitation can allow an attacker to run remote commands, including establishing a reverse shell. This issue affects Wirtualna Uczelnia versions up to wu#2016.437.295#0#20260327_105545

Affected products (as reported)

Vendor	Product	Versions
Simple SA	Wirtualna Uczelnia	0 – through wu#2016.437.295#0#20260327_105545

Weakness: CWE-1336 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:L/SI:L/SA:L

References

https://cert.pl/posts/2026/06/CVE-2026-34906 third-party-advisory
https://simple.com.pl/branze/edukacyjna/ product