cbcvebase.
CVE-2021-20254
published 2021-05-05

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…

PriorityP340medium6.8CVSS 3.1
AVNACHPRLUINSUCHIHAN
EPSS
1.62%
73.3th percentile
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.

Affected

18 ranges
VendorProductVersion rangeFixed in
debiandebian_linux
debiansamba< samba 2:4.13.5+dfsg-2 (bookworm)samba 2:4.13.5+dfsg-2 (bookworm)
fedoraprojectfedora
fedoraprojectfedora
msrcazl3_samba_4.18.3-1_on_azure_linux_3.0
msrcazure_linux_3.0_arm
msrcazure_linux_3.0_x64
redhatenterprise_linux
redhatenterprise_linux
sambasamba
sambasamba>= 0 < 2:4.13.5+dfsg-22:4.13.5+dfsg-2
sambasamba>= 0 < 2:4.13.5+dfsg-22:4.13.5+dfsg-2
sambasamba>= 0 < 2:4.13.5+dfsg-22:4.13.5+dfsg-2
sambasamba>= 0 < 2:4.13.5+dfsg-22:4.13.5+dfsg-2
sambasamba>= 0 < 2:4.3.11+dfsg-0ubuntu0.14.04.20+esm112:4.3.11+dfsg-0ubuntu0.14.04.20+esm11
sambasamba>= 3.6.0 < 4.12.154.12.15
sambasamba>= 4.13.0 < 4.13.84.13.8
sambasamba>= 4.14.0 < 4.14.44.14.4

CVSS provenance

nvdv3.16.8MEDIUMCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N
nvdv2.04.9MEDIUMAV:N/AC:M/Au:S/C:P/I:P/A:N
osv6.8MEDIUM
vendor_debian6.8MEDIUM
vendor_msrc6.8MEDIUM
vendor_redhat6.8MEDIUM
vendor_ubuntu4.3MEDIUM
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