{"id":"AZL-97548","summary":"CVE-2026-63387 affecting package ntp 4.2.8p17-2","details":"Libevent is an event notification library. Prior to 2.1.13 and 2.2.2-alpha, libevent has an off-by-one stack buffer overflow in evdns.c when dnsname_to_labels formats a name-bearing DNS record at the end of the 64 KB stack buffer allocated by evdns_server_request_format_response. The final-label check permits j plus label_len plus one to equal buf_len, after which the terminating null byte is written to buf[buf_len]. A crafted DNS server response containing PTR, CNAME, MX, NS, or SOA data can trigger the one-byte out-of-bounds write and crash or corrupt the process. This issue is fixed in versions 2.1.13 and 2.2.2-alpha.","modified":"2026-08-29T05:27:27Z","published":"2026-08-20T18:16:36Z","upstream":["CVE-2026-63387"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-63387"}],"affected":[{"package":{"name":"ntp","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/ntp"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"4.2.8p17-2"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-97548.json"}}],"schema_version":"1.9.0"}