UBUNTU-CVE-2021-3640

    Dashboard / Vulnerabilities / UBUNTU-CVE-2021-3640

    UBUNTU-CVE-2021-3640

    Published: 18 Jul 2021Last Modified: 9 Sept 2026
    Upstream:
    CVE-2021-3640
    Aliases:
    USN-5265-1
    USN-5267-1
    USN-5267-3

    Summary:

    Details: A flaw use-after-free in function sco_sock_sendmsg() of the Linux kernel HCI subsystem was found in the way user calls ioct UFFDIO_REGISTER or other way triggers race condition of the call sco_conn_del() together with the call sco_sock_sendmsg() with the expected controllable faulting memory page. A privileged local user could use this flaw to crash the system or escalate their privileges on the system.

    References: https://ubuntu.com/security/CVE-2021-3640, https://www.openwall.com/lists/oss-security/2021/07/22/1, https://x-lore.kernel.org/all/[email protected]/, https://x-lore.kernel.org/all/[email protected]/, https://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth-next.git/commit/?id=99c23da0eed4fd20cae8243f2b51e10e66aa0951, https://x-lore.kernel.org/all/[email protected]/, https://ubuntu.com/security/notices/USN-5265-1, https://ubuntu.com/security/notices/USN-5267-1, https://ubuntu.com/security/notices/USN-5268-1, https://ubuntu.com/security/notices/USN-5267-3, https://www.cve.org/CVERecord?id=CVE-2021-3640

    Affected packages

    Package

    Name: linux-azure

    Purl: pkg:deb/ubuntu/linux-azure?arch=source&distro=trusty%2Fesm

    Affected ranges

    Type: ECOSYSTEM

    Events:

    Introduced- 0
    Fixed -4.15.0-1130.143~14.04.1

    Affected versions

    4.15.0-1023.24~14.04.1
    4.15.0-1030.31~14.04.1
    4.15.0-1031.32~14.04.1
    4.15.0-1032.33~14.04.2
    4.15.0-1035.36~14.04.2
    4.15.0-1036.38~14.04.2
    4.15.0-1037.39~14.04.2
    4.15.0-1039.41~14.04.2
    4.15.0-1040.44~14.04.1
    4.15.0-1041.45~14.04.1
    4.15.0-1042.46~14.04.1
    4.15.0-1045.49~14.04.1
    4.15.0-1046.50~14.04.1
    4.15.0-1047.51~14.04.1
    4.15.0-1049.54~14.04.1
    4.15.0-1050.55~14.04.1
    4.15.0-1051.56~14.04.1
    4.15.0-1052.57~14.04.1
    4.15.0-1055.60~14.04.1
    4.15.0-1056.61~14.04.1
    4.15.0-1057.62~14.04.1
    4.15.0-1059.64~14.04.1
    4.15.0-1060.65~14.04.1
    4.15.0-1061.66~14.04.1
    4.15.0-1063.68~14.04.1
    4.15.0-1064.69~14.04.1
    4.15.0-1066.71~14.04.1
    4.15.0-1067.72~14.04.1
    4.15.0-1069.74~14.04.1
    4.15.0-1071.76~14.04.1
    4.15.0-1074.79~14.04.1
    4.15.0-1077.82~14.04.1
    4.15.0-1082.92~14.04.1
    4.15.0-1083.93~14.04.1
    4.15.0-1089.99~14.04.1
    4.15.0-1091.101~14.04.1
    4.15.0-1092.102~14.04.1
    4.15.0-1093.103~14.04.1
    4.15.0-1095.105~14.04.1
    4.15.0-1096.106~14.04.1
    4.15.0-1098.109~14.04.1
    4.15.0-1100.111~14.04.1
    4.15.0-1102.113~14.04.1
    4.15.0-1103.114~14.04.1
    4.15.0-1106.118~14.04.1
    4.15.0-1108.120~14.04.1
    4.15.0-1109.121~14.04.1
    4.15.0-1110.122~14.04.1
    4.15.0-1111.123~14.04.1
    4.15.0-1112.124~14.04.1
    4.15.0-1113.126~14.04.1
    4.15.0-1114.127~14.04.1
    4.15.0-1115.128~14.04.1
    4.15.0-1118.131~14.04.1
    4.15.0-1121.134~14.04.1
    4.15.0-1122.135~14.04.1
    4.15.0-1123.136~14.04.1
    4.15.0-1124.137~14.04.1
    4.15.0-1125.138~14.04.1
    4.15.0-1126.139~14.04.1
    4.15.0-1127.140~14.04.1
    4.15.0-1129.142~14.04.1

    Common Vulnerability Scoring System

    Attack Vector
    Network
    Adjacent
    Local
    Physical
    Privileges Required
    None
    Low
    High
    User Interaction
    None
    Required
    Scope
    Unchanged
    Changed
    Confidentiality
    None
    Low
    High
    Integrity
    None
    Low
    High
    Availability
    None
    Low
    High
    UBUNTU-CVE-2021-3640 | CVE-DB