CVE-2026-31845

CVE-2026-31845 is a critical-severity vulnerability with a CVSS 3.x base score of 9.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-79.

Key facts

Description

A reflected cross-site scripting (XSS) vulnerability exists in Rukovoditel CRM version 3.6.4 and earlier in the Zadarma telephony API endpoint (/api/tel/zadarma.php). The application directly reflects user-supplied input from the 'zd_echo' GET parameter into the HTTP response without proper sanitization, output encoding, or content-type restrictions. The vulnerable code is: if (isset($_GET['zd_echo'])) exit($_GET['zd_echo']); An unauthenticated attacker can exploit this issue by crafting a malicious URL containing JavaScript payloads. When a victim visits the link, the payload executes in the context of the application within the victim's browser, potentially leading to session hijacking, credential theft, phishing, or account takeover. The issue is fixed in version 3.7, which introduces proper input validation and output encoding to prevent script injection.

Frequently asked questions

What is CVE-2026-31845?
A reflected cross-site scripting (XSS) vulnerability exists in Rukovoditel CRM version 3.6.4 and earlier in the Zadarma telephony API endpoint (/api/tel/zadarma.php). The application directly reflects user-supplied input from the 'zd_echo' GET parameter into the HTTP response without proper sanitization, output encoding, or content-type restrictions. The vulnerable code is: if (isset($_GET['zd_echo'])) exit($_GET['zd_echo']); An unauthenticated attacker can exploit this issue by crafting a malicious URL containing JavaScript payloads. When a victim visits the link, the payload executes in the context of the application within the victim's browser, potentially leading to session hijacking, credential theft, phishing, or account takeover. The issue is fixed in version 3.7, which introduces proper input validation and output encoding to prevent script injection.
How severe is CVE-2026-31845?
CVE-2026-31845 has a CVSS 3.x base score of 9.3, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability none.
Is CVE-2026-31845 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (39th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-31845?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
Does CVE-2026-31845 have an EU (EUVD) identifier?
Yes. CVE-2026-31845 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-21682.
When was CVE-2026-31845 published?
CVE-2026-31845 was published on 2026-04-11 and last updated on 2026-06-17.

References

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