Critical UNKNOWN READ Vulnerability in libical: strncasecmp Function
Summary
OSV-2026-311: UNKNOWN READ in strncasecmp. Affects libical versions >= f8cb7b4349809e51bad3902d130804d31ede3116, < 0d3735426835aff0bd8151a0203e0720b157315f. Fixed in 0d3735426835aff0bd8151a0203e0720b157315f. How to fix ↓
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Background
libical is an open-source library designed for parsing and manipulating iCalendar data. It provides functionalities for handling calendar events, to-dos, and other scheduling information. The library is widely used in applications that require calendar integration. However, it is susceptible to a critical vulnerability that can lead to unexpected behavior and potential crashes.
Vulnerability Detail
The vulnerability identified as an UNKNOWN READ in the strncasecmp function originates from a flaw in the vcardcomponent_string_to_kind and _parse_vcard functions. This issue can lead to crashes when the library processes vCard data, potentially affecting applications that rely on libical for calendar functionalities. The vulnerability was reported through OSS-Fuzz, highlighting its severity and the need for immediate attention.
How To Fix
Minimum fixed version
0d3735426835aff0bd8151a0203e0720b157315f
This is the first release that contains the fix.
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Workaround
As a temporary workaround, users can avoid processing untrusted vCard data until the library is updated. This can help mitigate the risk of crashes while a permanent fix is being implemented.
Conclusion
In summary, the UNKNOWN READ vulnerability in the libical library poses a significant risk to applications that utilize its functionalities for calendar management. Immediate action is required to update to the patched version to prevent potential crashes and ensure stability. Users are encouraged to monitor their applications for vulnerabilities using tools like Vulert.
See every vulnerability recorded for libical →
FAQ
The UNKNOWN READ vulnerability allows for potential crashes when the strncasecmp function is called with invalid data, leading to unpredictable behavior in applications using libical.
You can use Vulert's playground at Vulert Scanner to check if your application is affected by this vulnerability without needing to sign up.
Failure to address this vulnerability may result in application crashes, data loss, and a compromised user experience, especially in calendar-related functionalities.
Yes, the fixed version of libical is 0d3735426835aff0bd8151a0203e0720b157315f. It is recommended to update to this version to mitigate the vulnerability.
Yes, you can report new vulnerabilities through the OSS-Fuzz platform or directly to the libical maintainers on their GitHub repository.
References
Related vulnerabilities
Recent vulnerabilities recorded for libical.
