vulnerability
Red Hat: CVE-2021-20254: CVE-2021-20254 samba: Negative idmap cache entries can cause incorrect group entries in the Samba file server process token (Multiple Advisories)
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 5 | (AV:N/AC:M/Au:S/C:P/I:P/A:N) | May 5, 2021 | Jun 9, 2021 | Aug 11, 2025 |
Severity
5
CVSS
(AV:N/AC:M/Au:S/C:P/I:P/A:N)
Published
May 5, 2021
Added
Jun 9, 2021
Modified
Aug 11, 2025
Description
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.
Solutions
no-fix-redhat-rpm-packageredhat-upgrade-ctdbredhat-upgrade-ctdb-debuginforedhat-upgrade-ctdb-testsredhat-upgrade-ctdb-tests-debuginforedhat-upgrade-libsmbclientredhat-upgrade-libsmbclient-debuginforedhat-upgrade-libsmbclient-develredhat-upgrade-libwbclientredhat-upgrade-libwbclient-debuginforedhat-upgrade-libwbclient-develredhat-upgrade-python3-sambaredhat-upgrade-python3-samba-debuginforedhat-upgrade-python3-samba-testredhat-upgrade-sambaredhat-upgrade-samba-clientredhat-upgrade-samba-client-debuginforedhat-upgrade-samba-client-libsredhat-upgrade-samba-client-libs-debuginforedhat-upgrade-samba-commonredhat-upgrade-samba-common-libsredhat-upgrade-samba-common-libs-debuginforedhat-upgrade-samba-common-toolsredhat-upgrade-samba-common-tools-debuginforedhat-upgrade-samba-dcredhat-upgrade-samba-dc-libsredhat-upgrade-samba-debuginforedhat-upgrade-samba-debugsourceredhat-upgrade-samba-develredhat-upgrade-samba-krb5-printingredhat-upgrade-samba-krb5-printing-debuginforedhat-upgrade-samba-libsredhat-upgrade-samba-libs-debuginforedhat-upgrade-samba-pidlredhat-upgrade-samba-pythonredhat-upgrade-samba-python-testredhat-upgrade-samba-testredhat-upgrade-samba-test-debuginforedhat-upgrade-samba-test-libsredhat-upgrade-samba-test-libs-debuginforedhat-upgrade-samba-vfs-glusterfsredhat-upgrade-samba-vfs-glusterfs-debuginforedhat-upgrade-samba-winbindredhat-upgrade-samba-winbind-clientsredhat-upgrade-samba-winbind-clients-debuginforedhat-upgrade-samba-winbind-debuginforedhat-upgrade-samba-winbind-krb5-locatorredhat-upgrade-samba-winbind-krb5-locator-debuginforedhat-upgrade-samba-winbind-modulesredhat-upgrade-samba-winbind-modules-debuginforedhat-upgrade-samba-winexeredhat-upgrade-samba-winexe-debuginfo
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