CVE-2001-0669
Various Intrusion Detection Systems (IDS) including (1) Cisco Secure Intrusion Detection System, (2) Cisco Catalyst 6000 Intrusion…
- Published
- Updated
- Reserved
- Assigned by
- mitre
Description
Various Intrusion Detection Systems (IDS) including (1) Cisco Secure Intrusion Detection System, (2) Cisco Catalyst 6000 Intrusion Detection System Module, (3) Dragon Sensor 4.x, (4) Snort before 1.8.1, (5) ISS RealSecure Network Sensor 5.x and 6.x before XPU 3.2, and (6) ISS RealSecure Server Sensor 5.5 and 6.0 for Windows, allow remote attackers to evade detection of HTTP attacks via non-standard "%u" Unicode encoding of ASCII characters in the requested URL.
Timeline
ID reserved
By mitre
- 46 days later
· 46 days later
Published
- 23 years later
· 23 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Modified | 2.0 | High7.5 | AV:N/AC:L/Au:N/C:P/I:P/A:P |
- EPSS (exploitation in 30 days)
- 4.4% · top 8.6% of all CVEs (8 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.5.
Weakness
- n/a
Affected products
n/a
- affected n/a
References (5)
- VU#548515 (opens in a new tab)third-party-advisoryx_refsource_CERT-VNx_transferred
- 3292 (opens in a new tab)vdb-entryx_refsource_BIDx_transferred
- 20010905 Cisco Secure Intrusion Detection System Signature Obfuscation Vulnerability (opens in a new tab)vendor-advisoryx_refsource_CISCOx_transferred
- 20010905 Multiple Vendor IDS Unicode Bypass Vulnerability (opens in a new tab)third-party-advisoryx_refsource_ISSx_transferred
- 20010905 %u encoding IDS bypass vulnerability (opens in a new tab)mailing-listx_refsource_BUGTRAQx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2001-0669)Record last updated .