Vulnerability Name:

CVE-2021-20316 (CCN-234227)

Assigned:2020-12-17
Published:2022-01-10
Updated:2022-08-26
Summary:A flaw was found in the way Samba handled file/directory metadata. This flaw allows an authenticated attacker with permissions to read or modify share metadata, to perform this operation outside of the share.
CVSS v3 Severity:6.8 Medium (CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N)
5.9 Medium (Temporal CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N/E:U/RL:O/RC:C)
Exploitability Metrics:Attack Vector (AV): Network
Attack Complexity (AC): High
Privileges Required (PR): Low
User Interaction (UI): None
Scope:Scope (S): Unchanged
Impact Metrics:Confidentiality (C): High
Integrity (I): High
Availibility (A): None
5.9 Medium (CCN CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:H/A:N)
5.2 Medium (CCN Temporal CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:H/A:N/E:U/RL:O/RC:C)
Exploitability Metrics:Attack Vector (AV): Network
Attack Complexity (AC): High
Privileges Required (PR): Low
User Interaction (UI): None
Scope:Scope (S): Unchanged
Impact Metrics:Confidentiality (C): Low
Integrity (I): High
Availibility (A): None
5.9 Medium (REDHAT CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:H/A:N)
5.2 Medium (REDHAT Temporal CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:H/A:N/E:U/RL:O/RC:C)
Exploitability Metrics:Attack Vector (AV): Network
Attack Complexity (AC): High
Privileges Required (PR): Low
User Interaction (UI): None
Scope:Scope (S): Unchanged
Impact Metrics:Confidentiality (C): Low
Integrity (I): High
Availibility (A): None
CVSS v2 Severity:5.6 Medium (CCN CVSS v2 Vector: AV:N/AC:H/Au:S/C:P/I:C/A:N)
Exploitability Metrics:Access Vector (AV): Network
Access Complexity (AC): High
Athentication (Au): Single_Instance
Impact Metrics:Confidentiality (C): Partial
Integrity (I): Complete
Availibility (A): None
Vulnerability Type:CWE-362
Vulnerability Consequences:Bypass Security
References:Source: MITRE
Type: CNA
CVE-2021-20316

Source: MISC
Type: Third Party Advisory
https://access.redhat.com/security/cve/CVE-2021-20316

Source: MISC
Type: Issue Tracking, Third Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2009673

Source: CCN
Type: The Samba-Bugzilla - Bug 14842
CVE-2021-20316 [SECURITY] Fileserver symlink metadata share escape

Source: MISC
Type: Issue Tracking, Vendor Advisory
https://bugzilla.samba.org/show_bug.cgi?id=14842

Source: XF
Type: UNKNOWN
samba-cve202120316-sec-bypass(234227)

Source: MISC
Type: Mitigation, Third Party Advisory
https://security-tracker.debian.org/tracker/CVE-2021-20316

Source: CCN
Type: Samba Web site
CVE-2021-20316.html

Source: MISC
Type: Vendor Advisory
https://www.samba.org/samba/security/CVE-2021-20316.html

Vulnerable Configuration:Configuration 1:
  • cpe:/a:samba:samba:*:*:*:*:*:*:*:* (Version < 4.15.0)

    • Configuration 2:
  • cpe:/o:debian:debian_linux:10.0:*:*:*:*:*:*:*
  • OR cpe:/o:debian:debian_linux:11.0:*:*:*:*:*:*:*

    • Configuration 3:
  • cpe:/a:redhat:virtualization_host:4.0:*:*:*:*:*:*:*
  • OR cpe:/o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*
  • OR cpe:/o:redhat:enterprise_linux_eus:8.6:*:*:*:*:*:*:*
  • OR cpe:/o:redhat:enterprise_linux_tus:8.6:*:*:*:*:*:*:*
  • OR cpe:/o:redhat:enterprise_linux_aus:8.6:*:*:*:*:*:*:*

    • Configuration RedHat 1:
  • cpe:/a:redhat:enterprise_linux:8:*:*:*:*:*:*:*

    • Configuration RedHat 2:
  • cpe:/a:redhat:enterprise_linux:8::appstream:*:*:*:*:*

    • Configuration RedHat 3:
  • cpe:/a:redhat:enterprise_linux:8::crb:*:*:*:*:*

    • Configuration RedHat 4:
  • cpe:/o:redhat:enterprise_linux:8:*:*:*:*:*:*:*

    • Configuration RedHat 5:
  • cpe:/o:redhat:enterprise_linux:8::baseos:*:*:*:*:*

    • Configuration CCN 1:
  • cpe:/a:samba:samba:4.14.0:-:*:*:*:*:*:*

    • * Denotes that component is vulnerable
    Oval Definitions
    Definition IDClassTitleLast Modified
    oval:com.redhat.rhsa:def:20222074
    P
    		RHSA-2022:2074: samba security, bug fix, and enhancement update (Moderate)
    2022-05-10
    oval:org.opensuse.security:def:6156
    P
    		Security update for samba (Critical)
    2022-02-14
    oval:org.opensuse.security:def:4303
    P
    		Security update for samba (Critical)
    2022-02-14
    oval:org.opensuse.security:def:5339
    P
    		Security update for samba (Critical)
    2022-02-14
    oval:org.opensuse.security:def:1757
    P
    		Security update for samba (Critical)
    2022-02-08
    oval:org.opensuse.security:def:102146
    P
    		Security update for samba (Critical)
    2022-02-08
    oval:org.opensuse.security:def:99206
    P
    		 (Critical)
    2022-02-08
    oval:org.opensuse.security:def:935
    P
    		Security update for samba (Critical)
    2022-02-08
    oval:org.opensuse.security:def:100410
    P
    		 (Critical)
    2022-02-08
    oval:org.opensuse.security:def:42332
    P
    		Security update for samba (Critical)
    2022-02-08
    oval:org.opensuse.security:def:102246
    P
    		Security update for samba (Critical)
    2022-02-08
    oval:org.opensuse.security:def:99480
    P
    		 (Critical)
    2022-02-08
    oval:org.opensuse.security:def:1586
    P
    		Security update for samba (Critical)
    2022-02-08
    oval:org.opensuse.security:def:100744
    P
    		 (Critical)
    2022-02-08
    oval:org.opensuse.security:def:102309
    P
    		Security update for samba (Critical)
    2022-02-08
    oval:org.opensuse.security:def:99742
    P
    		 (Critical)
    2022-02-08
    oval:org.opensuse.security:def:1685
    P
    		Security update for samba (Critical)
    2022-02-08
    oval:org.opensuse.security:def:101627
    P
    		Security update for samba (Critical)
    2022-02-08
    oval:org.opensuse.security:def:100072
    P
    		 (Critical)
    2022-02-08
    BACK
    samba samba *
    debian debian linux 10.0
    debian debian linux 11.0
    redhat virtualization host 4.0
    redhat enterprise linux 8.0
    redhat enterprise linux eus 8.6
    redhat enterprise linux tus 8.6
    redhat enterprise linux aus 8.6
    samba samba 4.14.0