{"id":"AZL-51768","summary":"CVE-2024-49987 affecting package kernel 5.15.200.1-1","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpftool: Fix undefined behavior in qsort(NULL, 0, ...)\n\nWhen netfilter has no entry to display, qsort is called with\nqsort(NULL, 0, ...). This results in undefined behavior, as UBSan\nreports:\n\nnet.c:827:2: runtime error: null pointer passed as argument 1, which is declared to never be null\n\nAlthough the C standard does not explicitly state whether calling qsort\nwith a NULL pointer when the size is 0 constitutes undefined behavior,\nSection 7.1.4 of the C standard (Use of library functions) mentions:\n\n\"Each of the following statements applies unless explicitly stated\notherwise in the detailed descriptions that follow: If an argument to a\nfunction has an invalid value (such as a value outside the domain of\nthe function, or a pointer outside the address space of the program, or\na null pointer, or a pointer to non-modifiable storage when the\ncorresponding parameter is not const-qualified) or a type (after\npromotion) not expected by a function with variable number of\narguments, the behavior is undefined.\"\n\nTo avoid this, add an early return when nf_link_info is NULL to prevent\ncalling qsort with a NULL pointer.","modified":"2026-04-01T05:20:46.027312Z","published":"2024-10-21T18:15:19Z","upstream":["CVE-2024-49987"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2024-49987"}],"affected":[{"package":{"name":"kernel","ecosystem":"Azure Linux:2","purl":"pkg:rpm/azure-linux/kernel"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"5.15.200.1-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-51768.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"}]}