CVE-2003-1263 in iCal
Summary
by MITRE
ICAL.EXE in iCal 3.7 allows remote attackers to cause a denial of service (crash) via a malformed HTTP request, possibly due to an invalid method name.
Be aware that VulDB is the high quality source for vulnerability data.
Analysis
by VulDB Data Team • 01/28/2025
The vulnerability identified as CVE-2003-1263 affects ICAL.EXE component within iCal 3.7 software, representing a significant security weakness that enables remote attackers to execute denial of service attacks. This flaw specifically manifests when the system processes malformed HTTP requests containing invalid method names, leading to application crashes and service unavailability. The vulnerability demonstrates a classic input validation failure where the application fails to properly sanitize or validate incoming HTTP method parameters before processing them.
The technical implementation of this vulnerability stems from inadequate boundary checking and input validation within the HTTP request parsing mechanism of iCal 3.7. When ICAL.EXE receives an HTTP request with a malformed method name, the application's request handler does not properly validate the method parameter against expected values or protocols. This parsing failure results in a buffer overflow or memory corruption scenario that ultimately causes the application to crash and terminate unexpectedly. The vulnerability operates at the application layer and requires no authentication or privileged access to exploit, making it particularly dangerous as it can be triggered remotely by any attacker with network access to the affected system.
From an operational perspective, this vulnerability creates substantial risk for organizations relying on iCal 3.7 for calendar services or web-based applications. The denial of service impact means that legitimate users cannot access calendar functionality or related services, potentially disrupting business operations and productivity. The remote exploitation capability amplifies the threat as attackers can trigger the vulnerability from anywhere on the network without physical access to the system. This vulnerability aligns with CWE-122, which describes buffer overflow conditions, and represents a specific instance of improper input validation that can lead to system instability. The attack pattern corresponds to techniques described in the ATT&CK framework under defensive evasion and denial of service tactics, where adversaries seek to disrupt services without necessarily gaining unauthorized access to system resources.
Mitigation strategies for CVE-2003-1263 should focus on immediate patching of the iCal 3.7 software to address the input validation flaw. Organizations should implement network-level protections such as firewalls and intrusion detection systems to monitor and filter malformed HTTP requests before they reach the vulnerable application. Additionally, configuring the application to run with restricted privileges and implementing application-level input sanitization can help reduce the impact of potential exploitation attempts. Regular security assessments and vulnerability scanning should be conducted to identify similar input validation issues in other applications. The remediation process should also include monitoring for any signs of exploitation attempts and implementing proper incident response procedures to quickly address any successful attacks that may occur.