Vulnerability Report

CVE-2021-20254

Title: Samba smbd Out-of-Bounds Read

Information Disclosure/Integrity

Proof Of Concept

No public PoC currently indexed for CVE-2021-20254.

CWE Category CWE-125
Published Date May 05, 2021
Modified Date Nov 21, 2024
Exploit Status Not Found
Score 6.8 CVSS v3.1
Exploit Probability (EPSS)
1.62%

Vulnerability Summary

CVE-2021-20254: A flaw was found in samba. The Samba smbd file server must map Windows group identities (SIDs) into unix group ids (gids). The code that performs this had a flaw that could allow it to read data beyond the end of the array in the case where a negative cache entry had been added to the mapping cache. This could cause the calling code to return those values into the process token that stores the group membership for a user. The highest threat from this vulnerability is to data confidentiality and integrity.

Impacted Vendors

S
samba 1
S
sgi 1

Reference Links

https://bugzilla.redhat.com/show_bug.cgi?id=1949442 https://lists.debian.org/debian-lts-announce/2021/05/msg00023.html https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/3EP2VJ73OVBPVSOSTVOMGIEQA3MWF6F7/ https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZAF6L2M6CNAJ2YYYGXPWETTW5YLCWTVT/ https://security.gentoo.org/glsa/202105-22 https://security.netapp.com/advisory/ntap-20210430-0001/ https://www.samba.org/samba/security/CVE-2021-20254.html https://bugzilla.redhat.com/show_bug.cgi?id=1949442 https://lists.debian.org/debian-lts-announce/2021/05/msg00023.html https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/3EP2VJ73OVBPVSOSTVOMGIEQA3MWF6F7/ https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZAF6L2M6CNAJ2YYYGXPWETTW5YLCWTVT/ https://security.gentoo.org/glsa/202105-22 https://security.netapp.com/advisory/ntap-20210430-0001/ https://www.samba.org/samba/security/CVE-2021-20254.html
CVSS v3.1
Source Entity [email protected]
Severity MEDIUM
6.8
Attack Vector
NETWORK
Complexity
HIGH
Privileges
N/A
Interaction
NONE
Confidentiality
N/A
Integrity
N/A
Availability
N/A
Scope
UNCHANGED
RAW VECTOR CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N
CVSS v2.0
Source Entity [email protected]
Severity MEDIUM
4.9
Access Vector
N/A
Authentication
N/A
RAW VECTOR AV:N/AC:M/Au:S/C:P/I:P/A:N

Associated Attack Patterns (CAPEC)

Total: Patterns

CVE-2021-20254 Exploits & PoCs (Proof Of Concept)

No public PoCs found in our database for this CVE.

MODIFIED

Vulnerability data or affected products updated.

PUBLISHED

Vulnerability first announced in NVD.

Attack Vector Matrix

Access Vector NETWORK
Complexity HIGH
Privileges N/A
Interaction NONE
CVSS Vector String CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N

Affected Stack

No specific products linked.