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Vulnerability record · CVE-2003-0866 · published 17 November 2003

CVE-2003-0866: Apache tomcat vulnerability

Apache · Tomcat

The Catalina org.apache.catalina.connector.http package in Tomcat 4.0.x up to 4.0.3 allows remote attackers to cause a denial of service via several requests that do not follow the HTTP protocol, which causes Tomcat to reject later requests.

5.0 CVSS 2.0 Medium EPSS 35% · top 1.6%
5.0CVSS 2.0 base score
35%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
24References, 2 tagged exploit
16 Jun 2026Last modified by NVD

Description

The Catalina org.apache.catalina.connector.http package in Tomcat 4.0.x up to 4.0.3 allows remote attackers to cause a denial of service via several requests that do not follow the HTTP protocol, which causes Tomcat to reject later requests.

AV:N/AC:L/Au:N/C:N/I:N/A:P

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=215506 ExploitPatchVendor Advisory
http://secunia.com/advisories/30899
http://secunia.com/advisories/30908
http://sunsolve.sun.com/search/document.do?assetkey=1-26-239312-1
http://tomcat.apache.org/security-4.html
http://www.debian.org/security/2003/dsa-395 PatchVendor Advisory
http://www.securityfocus.com/bid/8824 PatchVendor Advisory
http://www.vupen.com/english/advisories/2008/1979/references
https://exchange.xforce.ibmcloud.com/vulnerabilities/13429
https://lists.apache.org/thread.html/29dc6c2b625789e70a9c4756b5a327e6547273ff8bde7e0327af48c5%40%3Cdev.tomcat.apache.org
https://lists.apache.org/thread.html/c62b0e3a7bf23342352a5810c640a94b6db69957c5c19db507004d74%40%3Cdev.tomcat.apache.org
https://lists.apache.org/thread.html/rb71997f506c6cc8b530dd845c084995a9878098846c7b4eacfae8db3%40%3Cdev.tomcat.apache.or
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=215506 ExploitPatchVendor Advisory
http://secunia.com/advisories/30899
http://secunia.com/advisories/30908
http://sunsolve.sun.com/search/document.do?assetkey=1-26-239312-1
http://tomcat.apache.org/security-4.html
http://www.debian.org/security/2003/dsa-395 PatchVendor Advisory
http://www.securityfocus.com/bid/8824 PatchVendor Advisory
http://www.vupen.com/english/advisories/2008/1979/references
https://exchange.xforce.ibmcloud.com/vulnerabilities/13429
https://lists.apache.org/thread.html/29dc6c2b625789e70a9c4756b5a327e6547273ff8bde7e0327af48c5%40%3Cdev.tomcat.apache.org
https://lists.apache.org/thread.html/c62b0e3a7bf23342352a5810c640a94b6db69957c5c19db507004d74%40%3Cdev.tomcat.apache.org
https://lists.apache.org/thread.html/rb71997f506c6cc8b530dd845c084995a9878098846c7b4eacfae8db3%40%3Cdev.tomcat.apache.or

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Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2003-0866), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.