{"api_version":"1","generated_at":"2026-04-23T03:26:34+00:00","cve":"CVE-2021-44538","urls":{"html":"https://cve.report/CVE-2021-44538","api":"https://cve.report/api/cve/CVE-2021-44538.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2021-44538","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2021-44538"},"summary":{"title":"CVE-2021-44538","description":"The olm_session_describe function in Matrix libolm before 3.2.7 is vulnerable to a buffer overflow. The Olm session object represents a cryptographic channel between two parties. Therefore, its state is partially controllable by the remote party of the channel. Attackers can construct a crafted sequence of messages to manipulate the state of the receiver's session in such a way that, for some buffer sizes, a buffer overflow happens on a call to olm_session_describe. Furthermore, safe buffer sizes were undocumented. The overflow content is partially controllable by the attacker and limited to ASCII spaces and digits. 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