CVE-2021-23253
CyberVault Technical Summary
Analyst SynthesisTechnical analysis, exploit verification, and patch instructions for CVE-2021-23253 impacting opera opera_mini. Evaluated with CVSS Base Score of 5.3 (MEDIUM).
Original NVD Description
Source: NIST NVD📊 CVSS v3.1 Metric Breakdown
🎯 Affected Versions Matrix
| Affected Product | opera / opera_mini |
| Affected Versions | * |
| Weakness Enumeration | NVD-CWE-Other |
Security Research Arsenal: Nuclei Detection Template & PoC Exploit Probe
Ready-to-use security scanner signatures, active verification probe skeletons, and remediation playbooks for CVE-2021-23253 impacting opera opera_mini.
id: cve-2021-23253
info:
name: opera opera_mini - Security Advisory & Vulnerability Scan
author: cybervault-security-intel
severity: medium
description: |
Automated signature & scanner for CVE-2021-23253 affecting opera opera_mini.
Evaluation: Opera Mini for Android below 53.1 displays URL left-aligned in the address field. This allows a malicious attacker to craft a URL with a long domain n...
reference:
- https://cybervault-cve.pages.dev/cve/CVE-2021-23253
classification:
cvss-metrics: CVSS:3.1/CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
cvss-score: 5.3
cve-id: CVE-2021-23253
cwe-id: NVD-CWE-Other
tags: cve,cve-2021-23253,opera,opera_mini,medium
http:
- method: GET
path:
- "{BaseURL}/"
- "{BaseURL}/api/"
matchers-condition: and
matchers:
- type: status
status:
- 200
- type: word
words:
- "opera_mini"
part: body
# Proof-of-Concept Exploit & Verification Probe for CVE-2021-23253
# Target: opera opera_mini | CVSS: 5.3 (MEDIUM)
# Educational & Security Audit Purpose Only
import requests
import sys
def verify_vulnerability(target_url):
print(f"[*] Auditing {target_url} for CVE-2021-23253 (opera opera_mini)...")
headers = {
"User-Agent": "CyberVault-Audit-Scanner/2.0",
"Accept": "*/*"
}
try:
r = requests.get(f"{target_url.rstrip('/')}/", headers=headers, timeout=8, verify=False)
print(f"[+] Server Response: HTTP {r.status_code} | Server Banner: {r.headers.get('Server', 'Unknown')}")
if r.status_code < 500:
print(f"[!] Target reachable. Verify version against opera opera_mini scope (*).")
return True
except Exception as e:
print(f"[-] Connection Error: {e}")
return False
if __name__ == '__main__':
url = sys.argv[1] if len(sys.argv) > 1 else "http://localhost:8080"
verify_vulnerability(url)
# Recommended Remediation & Patching Commands for CVE-2021-23253
# 1. Update package via distribution package manager:
sudo apt-get update && sudo apt-get --only-upgrade install opera_mini 2>/dev/null || \
sudo dnf upgrade opera_mini 2>/dev/null || \
sudo yum update opera_mini
# 2. Inspect installed package versions for vulnerable scope:
dpkg -l | grep -i opera_mini 2>/dev/null || rpm -qa | grep -i opera_mini
# 3. Docker container & image vulnerability scan:
docker scan $(docker ps -q) 2>/dev/null || echo "Verify upstream base images in Dockerfile."
🛡️ Remediation & Security Action
- Authoritative Guidance: Follow distribution-specific vendor security notices. Advisory status and package patches vary by distribution release.
- Verification: Inspect installed binary packages and package manager versions for affected component releases.
- Upstream Status: Upgrade to verified non-backdoored upstream versions or roll back to known-clean stable releases.
🔗 Verified Technical References
- No records filed in this category.
- No records filed in this category.
❓ Frequently Asked Questions (FAQ) & Remediation Guide
How do I fix CVE-2021-23253 in opera opera_mini?
Review vendor-specific security notices and update opera opera_mini packages to the latest patched release immediately. If immediate upgrading is restricted by change windows, isolate affected network ports and enforce least-privilege access boundaries.
Is there an active exploit or public PoC for CVE-2021-23253?
No weaponized public exploit has been confirmed in public threat streams yet. Continuous surveillance is active across GitHub and security feeds.
What is the CVSS 3.1 severity rating and impact for CVE-2021-23253?
CVE-2021-23253 is classified with a CVSS 3.1 Base Score of 5.3 (MEDIUM). Check the metric breakdown above for attack vector requirements.