CVSS2
Attack Vector
NETWORK
Attack Complexity
MEDIUM
Authentication
SINGLE
Confidentiality Impact
PARTIAL
Integrity Impact
PARTIAL
Availability Impact
NONE
AV:N/AC:M/Au:S/C:P/I:P/A:N
CVSS3
Attack Vector
NETWORK
Attack Complexity
HIGH
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
NONE
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N
AI Score
Confidence
High
EPSS
Percentile
74.4%
Issue Overview:
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. (CVE-2021-20254)
Affected Packages:
samba
Note:
This advisory is applicable to Amazon Linux 2 (AL2) Core repository. Visit this FAQ section for the difference between AL2 Core and AL2 Extras advisories.
Issue Correction:
Run yum update samba to update your system.
New Packages:
aarch64:
samba-4.10.16-15.amzn2.0.1.aarch64
samba-client-4.10.16-15.amzn2.0.1.aarch64
samba-client-libs-4.10.16-15.amzn2.0.1.aarch64
samba-common-libs-4.10.16-15.amzn2.0.1.aarch64
samba-common-tools-4.10.16-15.amzn2.0.1.aarch64
samba-dc-4.10.16-15.amzn2.0.1.aarch64
samba-dc-libs-4.10.16-15.amzn2.0.1.aarch64
samba-devel-4.10.16-15.amzn2.0.1.aarch64
samba-krb5-printing-4.10.16-15.amzn2.0.1.aarch64
samba-libs-4.10.16-15.amzn2.0.1.aarch64
libsmbclient-4.10.16-15.amzn2.0.1.aarch64
libsmbclient-devel-4.10.16-15.amzn2.0.1.aarch64
libwbclient-4.10.16-15.amzn2.0.1.aarch64
libwbclient-devel-4.10.16-15.amzn2.0.1.aarch64
samba-python-4.10.16-15.amzn2.0.1.aarch64
samba-python-test-4.10.16-15.amzn2.0.1.aarch64
samba-test-4.10.16-15.amzn2.0.1.aarch64
samba-test-libs-4.10.16-15.amzn2.0.1.aarch64
samba-winbind-4.10.16-15.amzn2.0.1.aarch64
samba-winbind-clients-4.10.16-15.amzn2.0.1.aarch64
samba-winbind-krb5-locator-4.10.16-15.amzn2.0.1.aarch64
samba-winbind-modules-4.10.16-15.amzn2.0.1.aarch64
ctdb-4.10.16-15.amzn2.0.1.aarch64
ctdb-tests-4.10.16-15.amzn2.0.1.aarch64
samba-debuginfo-4.10.16-15.amzn2.0.1.aarch64
i686:
samba-4.10.16-15.amzn2.0.1.i686
samba-client-4.10.16-15.amzn2.0.1.i686
samba-client-libs-4.10.16-15.amzn2.0.1.i686
samba-common-libs-4.10.16-15.amzn2.0.1.i686
samba-common-tools-4.10.16-15.amzn2.0.1.i686
samba-dc-4.10.16-15.amzn2.0.1.i686
samba-dc-libs-4.10.16-15.amzn2.0.1.i686
samba-devel-4.10.16-15.amzn2.0.1.i686
samba-krb5-printing-4.10.16-15.amzn2.0.1.i686
samba-libs-4.10.16-15.amzn2.0.1.i686
libsmbclient-4.10.16-15.amzn2.0.1.i686
libsmbclient-devel-4.10.16-15.amzn2.0.1.i686
libwbclient-4.10.16-15.amzn2.0.1.i686
libwbclient-devel-4.10.16-15.amzn2.0.1.i686
samba-python-4.10.16-15.amzn2.0.1.i686
samba-python-test-4.10.16-15.amzn2.0.1.i686
samba-test-4.10.16-15.amzn2.0.1.i686
samba-test-libs-4.10.16-15.amzn2.0.1.i686
samba-winbind-4.10.16-15.amzn2.0.1.i686
samba-winbind-clients-4.10.16-15.amzn2.0.1.i686
samba-winbind-krb5-locator-4.10.16-15.amzn2.0.1.i686
samba-winbind-modules-4.10.16-15.amzn2.0.1.i686
ctdb-4.10.16-15.amzn2.0.1.i686
ctdb-tests-4.10.16-15.amzn2.0.1.i686
samba-debuginfo-4.10.16-15.amzn2.0.1.i686
noarch:
samba-common-4.10.16-15.amzn2.0.1.noarch
samba-pidl-4.10.16-15.amzn2.0.1.noarch
src:
samba-4.10.16-15.amzn2.0.1.src
x86_64:
samba-4.10.16-15.amzn2.0.1.x86_64
samba-client-4.10.16-15.amzn2.0.1.x86_64
samba-client-libs-4.10.16-15.amzn2.0.1.x86_64
samba-common-libs-4.10.16-15.amzn2.0.1.x86_64
samba-common-tools-4.10.16-15.amzn2.0.1.x86_64
samba-dc-4.10.16-15.amzn2.0.1.x86_64
samba-dc-libs-4.10.16-15.amzn2.0.1.x86_64
samba-devel-4.10.16-15.amzn2.0.1.x86_64
samba-vfs-glusterfs-4.10.16-15.amzn2.0.1.x86_64
samba-krb5-printing-4.10.16-15.amzn2.0.1.x86_64
samba-libs-4.10.16-15.amzn2.0.1.x86_64
libsmbclient-4.10.16-15.amzn2.0.1.x86_64
libsmbclient-devel-4.10.16-15.amzn2.0.1.x86_64
libwbclient-4.10.16-15.amzn2.0.1.x86_64
libwbclient-devel-4.10.16-15.amzn2.0.1.x86_64
samba-python-4.10.16-15.amzn2.0.1.x86_64
samba-python-test-4.10.16-15.amzn2.0.1.x86_64
samba-test-4.10.16-15.amzn2.0.1.x86_64
samba-test-libs-4.10.16-15.amzn2.0.1.x86_64
samba-winbind-4.10.16-15.amzn2.0.1.x86_64
samba-winbind-clients-4.10.16-15.amzn2.0.1.x86_64
samba-winbind-krb5-locator-4.10.16-15.amzn2.0.1.x86_64
samba-winbind-modules-4.10.16-15.amzn2.0.1.x86_64
ctdb-4.10.16-15.amzn2.0.1.x86_64
ctdb-tests-4.10.16-15.amzn2.0.1.x86_64
samba-debuginfo-4.10.16-15.amzn2.0.1.x86_64
Red Hat: CVE-2021-20254
Mitre: CVE-2021-20254
CVSS2
Attack Vector
NETWORK
Attack Complexity
MEDIUM
Authentication
SINGLE
Confidentiality Impact
PARTIAL
Integrity Impact
PARTIAL
Availability Impact
NONE
AV:N/AC:M/Au:S/C:P/I:P/A:N
CVSS3
Attack Vector
NETWORK
Attack Complexity
HIGH
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
NONE
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N
AI Score
Confidence
High
EPSS
Percentile
74.4%