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    Dashboard / CVE / CVE-2021-33909

    CVE-2021-33909

    fs/seq_file.c in the Linux kernel 3.16 through 5.13.x before 5.13.4 does not properly restrict seq buffer allocations, leading to an integer overflow, an Out-of-bounds Write, and escalation to root by an unprivileged user, aka CID-8cae8cd89f05.

    Published:Jul 20, 2021
    Last Modified:Nov 21, 2024
    EPS:Jul 20, 2021
    EPSS Score:0.03537
    CVSS Score:7.8

    Affected Products

    Vendor
    Debian
    Product
    Debian Linux
    Vendor
    Fedoraproject
    Product
    Fedora
    Vendor
    Linux
    Product
    Linux Kernel
    Vendor
    Netapp
    Product
    Hci Management Node
    Vendor
    Netapp
    Product
    Solidfire
    Vendor
    Oracle
    Product
    Communications Session Border Controller
    Vendor
    Redhat
    Product
    Enterprise Linux
    Vendor
    Redhat
    Product
    Rhel Aus
    Vendor
    Redhat
    Product
    Rhel E4s
    Vendor
    Redhat
    Product
    Rhel Els
    Vendor
    Redhat
    Product
    Rhel Eus
    Vendor
    Redhat
    Product
    Rhel Extras Rt
    Vendor
    Redhat
    Product
    Rhel Tus
    Vendor
    Redhat
    Product
    Rhev Hypervisor
    Vendor
    Sonicwall
    Product
    Sma1000
    Vendor
    Sonicwall
    Product
    Sma1000 Firmware

    Exploits

    http://packetstormsecurity.com/files/163621/Sequoia-A-Deep-Root-In-Linuxs-Filesystem-Layer.htmlhttps://www.openwall.com/lists/oss-security/2021/07/20/1http://packetstormsecurity.com/files/163621/Sequoia-A-Deep-Root-In-Linuxs-Filesystem-Layer.htmlhttps://www.openwall.com/lists/oss-security/2021/07/20/1https://github.com/baerwolf/cve-2021-33909https://github.com/bbinfosec43/CVE-2021-33909https://github.com/ChrisTheCoolHut/CVE-2021-33909https://github.com/Liang2580/CVE-2021-33909

    Common Attack Pattern Enumeration and Classification (CAPEC)

    CAPEC-92 Forced Integer Overflow

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    References

    http://packetstormsecurity.com/files/163621/Sequoia-A-Deep-Root-In-Linuxs-Filesystem-Layer.html
    http://packetstormsecurity.com/files/163671/Kernel-Live-Patch-Security-Notice-LSN-0079-1.html
    http://packetstormsecurity.com/files/164155/Kernel-Live-Patch-Security-Notice-LSN-0081-1.html
    http://packetstormsecurity.com/files/165477/Kernel-Live-Patch-Security-Notice-LSN-0083-1.html
    http://www.openwall.com/lists/oss-security/2021/07/22/7
    http://www.openwall.com/lists/oss-security/2021/08/25/10
    http://www.openwall.com/lists/oss-security/2021/09/17/2
    http://www.openwall.com/lists/oss-security/2021/09/17/4
    http://www.openwall.com/lists/oss-security/2021/09/21/1
    https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.13.4
    https://github.com/torvalds/linux/commit/8cae8cd89f05f6de223d63e6d15e31c8ba9cf53b
    https://lists.debian.org/debian-lts-announce/2021/07/msg00014.html
    https://lists.debian.org/debian-lts-announce/2021/07/msg00015.html
    https://lists.debian.org/debian-lts-announce/2021/07/msg00016.html
    https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/Z4UHHIGISO3FVRF4CQNJS4IKA25ATSFU/
    https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2022-0015
    https://security.netapp.com/advisory/ntap-20210819-0004/
    https://www.debian.org/security/2021/dsa-4941
    https://www.openwall.com/lists/oss-security/2021/07/20/1
    https://www.oracle.com/security-alerts/cpujan2022.html
    http://packetstormsecurity.com/files/163621/Sequoia-A-Deep-Root-In-Linuxs-Filesystem-Layer.html
    http://packetstormsecurity.com/files/163671/Kernel-Live-Patch-Security-Notice-LSN-0079-1.html
    http://packetstormsecurity.com/files/164155/Kernel-Live-Patch-Security-Notice-LSN-0081-1.html
    http://packetstormsecurity.com/files/165477/Kernel-Live-Patch-Security-Notice-LSN-0083-1.html
    http://www.openwall.com/lists/oss-security/2021/07/22/7
    http://www.openwall.com/lists/oss-security/2021/08/25/10
    http://www.openwall.com/lists/oss-security/2021/09/17/2
    http://www.openwall.com/lists/oss-security/2021/09/17/4
    http://www.openwall.com/lists/oss-security/2021/09/21/1
    https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.13.4
    https://github.com/torvalds/linux/commit/8cae8cd89f05f6de223d63e6d15e31c8ba9cf53b
    https://lists.debian.org/debian-lts-announce/2021/07/msg00014.html
    https://lists.debian.org/debian-lts-announce/2021/07/msg00015.html
    https://lists.debian.org/debian-lts-announce/2021/07/msg00016.html
    https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/Z4UHHIGISO3FVRF4CQNJS4IKA25ATSFU/
    https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2022-0015
    https://security.netapp.com/advisory/ntap-20210819-0004/
    https://www.debian.org/security/2021/dsa-4941
    https://www.openwall.com/lists/oss-security/2021/07/20/1
    https://www.oracle.com/security-alerts/cpujan2022.html

    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