UBUNTU-CVE-2021-20321

    Dashboard / Vulnerabilities / UBUNTU-CVE-2021-20321

    UBUNTU-CVE-2021-20321

    Published: 18 Oct 2021Last Modified: 9 Sept 2026
    Upstream:
    CVE-2021-20321
    Aliases:
    USN-5208-1
    USN-5209-1
    USN-5210-1

    Summary:

    Details: A race condition accessing file object in the Linux kernel OverlayFS subsystem was found in the way users do rename in specific way with OverlayFS. A local user could use this flaw to crash the system.

    References: https://ubuntu.com/security/CVE-2021-20321, https://git.kernel.org/linus/a295aef603e109a47af355477326bd41151765b6, https://ubuntu.com/security/notices/USN-5208-1, https://ubuntu.com/security/notices/USN-5209-1, https://ubuntu.com/security/notices/USN-5210-1, https://ubuntu.com/security/notices/USN-5218-1, https://ubuntu.com/security/notices/USN-6221-1, https://www.cve.org/CVERecord?id=CVE-2021-20321

    Affected packages

    Package

    Name: linux-aws

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

    Affected ranges

    Type: ECOSYSTEM

    Events:

    Introduced- 0
    Fixed -4.4.0-1120.126

    Affected versions

    4.4.0-1002.2
    4.4.0-1003.3
    4.4.0-1005.5
    4.4.0-1006.6
    4.4.0-1009.9
    4.4.0-1010.10
    4.4.0-1011.11
    4.4.0-1012.12
    4.4.0-1014.14
    4.4.0-1016.16
    4.4.0-1017.17
    4.4.0-1019.19
    4.4.0-1022.22
    4.4.0-1023.23
    4.4.0-1024.25
    4.4.0-1025.26
    4.4.0-1027.30
    4.4.0-1028.31
    4.4.0-1029.32
    4.4.0-1031.34
    4.4.0-1032.35
    4.4.0-1034.37
    4.4.0-1036.39
    4.4.0-1037.40
    4.4.0-1038.41
    4.4.0-1039.42
    4.4.0-1040.43
    4.4.0-1042.45
    4.4.0-1044.47
    4.4.0-1045.48
    4.4.0-1046.50
    4.4.0-1048.52
    4.4.0-1050.54
    4.4.0-1052.56
    4.4.0-1054.58
    4.4.0-1055.59
    4.4.0-1056.60
    4.4.0-1058.62
    4.4.0-1059.63
    4.4.0-1060.64
    4.4.0-1061.65
    4.4.0-1062.66
    4.4.0-1064.68
    4.4.0-1065.69
    4.4.0-1066.70
    4.4.0-1067.71
    4.4.0-1073.77
    4.4.0-1074.78
    4.4.0-1075.79
    4.4.0-1076.80
    4.4.0-1077.81
    4.4.0-1078.82
    4.4.0-1081.85
    4.4.0-1082.86
    4.4.0-1083.87
    4.4.0-1085.89
    4.4.0-1086.90
    4.4.0-1087.91
    4.4.0-1088.92
    4.4.0-1090.94
    4.4.0-1091.95
    4.4.0-1092.96
    4.4.0-1093.97
    4.4.0-1094.99
    4.4.0-1095.100
    4.4.0-1096.101
    4.4.0-1097.102
    4.4.0-1098.103
    4.4.0-1099.104
    4.4.0-1101.106
    4.4.0-1102.107
    4.4.0-1103.108
    4.4.0-1104.109
    4.4.0-1107.113
    4.4.0-1109.115
    4.4.0-1110.116
    4.4.0-1111.117
    4.4.0-1112.118
    4.4.0-1113.119
    4.4.0-1114.120
    4.4.0-1115.121
    4.4.0-1116.122
    4.4.0-1117.123
    4.4.0-1118.124
    4.4.0-1119.125

    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-2021-20321 | CVE-DB