CVE-2001-0537
Confirmed PUBLISHEDHTTP server for Cisco IOS 11.3 to 12.2 allows attackers to bypass authentication and execute arbitrary commands, when local authorization is being...
Recommended Action
Prioritize immediate patching and validate internet-facing exposure. Monitor for matching exploitation attempts in your environment.
At a Glance
HTTP server for Cisco IOS 11.3 to 12.2 allows attackers to bypass authentication and execute arbitrary commands, when local authorization is being used, by specifying a high access level in the URL.
- CVE Published
- Mar 09, 2002
- Exploitation Reported
- Jun 21, 2025
- CVSS
- 9.3 High
- EPSS
- 68.5%
CVE References
- 20010627 IOS HTTP authorization vulnerability cisco.com · Vendor Advisory http://www.cisco.com/warp/public/707/IOS-httplevel-pub.html
- CA-2001-14 cert.org · Third-Party Advisory http://www.cert.org/advisories/CA-2001-14.html
- L-106 ciac.org · Third-Party Advisory http://www.ciac.org/ciac/bulletins/l-106.shtml
- 578 osvdb.org · VDB Entry http://www.osvdb.org/578
- 2936 securityfocus.com · VDB Entry http://www.securityfocus.com/bid/2936
Show 5 more references
- cisco-ios-admin-access(6749) exchange.xforce.ibmcloud.com · VDB Entry https://exchange.xforce.ibmcloud.com/vulnerabilities/6749
- 20010629 Re: Cisco Security Advisory: IOS HTTP authorization vulnerability securityfocus.com · Mailing List http://www.securityfocus.com/archive/1/4.3.2.7.2.20010629095801.0c3e6...
- 20010702 ios-http-auth.sh securityfocus.com · Mailing List http://www.securityfocus.com/archive/1/20010703011650.60515.qmail%40w...
- 20010702 Cisco IOS HTTP Configuration Exploit securityfocus.com · Mailing List http://www.securityfocus.com/archive/1/1601227034.20010702112207%40ol...
- 20010702 Cisco device HTTP exploit... securityfocus.com · Mailing List http://www.securityfocus.com/archive/1/Pine.LNX.3.96.1010702134611.22...
Known Exploited Vulnerability Sources
Catalogues that list this CVE as a known exploited vulnerability.
Per-source evidence links for KEV attestations are available through the KEVIntel Pro API.
Learn about Pro API access| Source | Added |
|---|---|
| The Shadowserver First | 2025-06-21 00:00 UTC |
| KEVIntel | 2026-07-31 10:42 UTC |
Operational indicators for this CVE are listed on the Detection tab.
Observed Exploitation Attempts
Exploitation attempts against this vulnerability observed first-hand by KEVIntel private honeypots over the last 30 days.
- Attempts Observed
- 25
- Unique Attacker IPs
- 7
- Attacker Countries
- 🇩🇪 🇫🇷 🇯🇵 🇳🇱 🇵🇱 🇸🇨
- Sensors Observed
- 16
Exploitation Attempts Over the Last 34 Days
First observed (all time) 2026-07-02 13:29 UTC · Last observed 2026-08-02 23:32 UTC
See more exploitation detail
- Pro — sensor software/region breakdown and 24h/7d window summaries.
- Enterprise — raw attacker IPs, request paths, User-Agents, and payloads.
Indicators of Compromise (IoCs)
Attacker IP IoCs observed in KEVIntel sensors are available to Pro and Enterprise accounts on the Detection tab and through the Pro API.
Learn about Pro API accessObserved Detection Signals (30d)
Aggregate counts from KEVIntel sensor telemetry for this CVE.
- Distinct request targets
- 3
- Distinct User-Agents
- 7
The specific request targets and User-Agents attackers are using are available on Pro and Enterprise plans.
Scanner Artifacts
Scanner and exploit-framework references linked to this CVE.
| Scanner | Reference | Detected |
|---|---|---|
| Nuclei | https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2001/CVE-2001-0537.yaml | Apr 25, 2025 |
Virtual Patch
Compensating WAF rules to help reduce exposure to this CVE. Rule content and deployable vendor exports are available with KEVIntel Enterprise.
KEVIntel does not currently have a virtual patch for this CVE. When available, KEVIntel virtual patches ship as deployable ModSecurity, Cloudflare, and AWS WAF rules.
Enterprise feature. Virtual patch rule content and deployable vendor exports (ModSecurity, Cloudflare, AWS WAF) are available to KEVIntel Enterprise users.
CVSS Scores
AV:N/AC:M/Au:N/C:C/I:C/A:C
Exploitation Status
Exploited in the wild
Recorded 2025-06-21 00:00:00 UTC · The Shadowserver
Active exploitation observed
Recorded 2026-07-02 13:29:31 UTC · KEVIntel sensor
Proof of concept available
Recorded 2026-06-12 14:19:58 UTC · Nuclei Templates
Weaknesses (CWE)
-
Improper Authentication
Scanner Integrations
Nuclei, Metasploit, and other scanner references for this CVE are listed on the Detection tab.
Potential Proof of Concepts
These PoCs are unverified and could contain malware. Use at your own risk.
nuclei · Created Unknown
Timeline
Key exploitation, disclosure, scanner coverage, and KEV attestation events for this CVE.
-
13:29 UTC about 1 month ago13:29 UTC · about 1 month ago
Observed by KEVIntel sensors
Evidence-backed exploitation signal
-
13:29 UTC about 1 month ago13:29 UTC · about 1 month ago
Indicators of compromise added (11)
Indicators of compromise recorded
-
14:19 UTC about 2 months ago14:19 UTC · about 2 months ago
Public PoC available
Public proof-of-concept code published
-
00:00 UTC about 1 year ago00:00 UTC · about 1 year ago
Added to KEVIntel KEV Feed
High-confidence, third-party attested exploitation
-
00:00 UTC over 1 year ago00:00 UTC · over 1 year ago
Nuclei template available
Scanner coverage available
-
05:00 UTC over 24 years ago05:00 UTC · over 24 years ago
CVE published
Vulnerability disclosed publicly
-
00:00 UTC about 25 years ago00:00 UTC · about 25 years ago
CVE ID reserved
Identifier reserved by the CNA
Automate This Intelligence with the Pro API
Confidence scoring, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.
Pro API Example
GET /api/v2/pro/kevs/CVE-2001-0537
{
"cve_id": "CVE-2001-0537",
"title": "HTTP server for Cisco IOS 11.3 to 12.2 allows attackers to bypass authenticat...",
"affected_vendor": "Cisco",
"affected_product": "IOS",
"affected_versions": [
{ "vendor": "...", "product": "...", "status": "affected", "display_label": "..." }
],
"confidence": "Confirmed",
"cvss_score": 9.3,
"epss_score": 0.6845,
"exploit_status": {
"exploited_in_the_wild": true,
"active_exploitation_observed": true
},
"sensor_telemetry": { "...": "Pro API fields" },
"proof_of_concepts": [ "..." ],
"scanner_integrations": [ "..." ]
}