CVE-2021-20251
published 2023-03-06CVE-2021-20251: A flaw was found in samba. A race condition in the password lockout code may lead to the risk of brute force attacks being successful if special conditions are…
PriorityP428medium5.9CVSS 3.1
AVNACHPRNUINSUCNIHAN
EPSS
0.76%
51.4th percentile
A flaw was found in samba. A race condition in the password lockout code may lead to the risk of brute force attacks being successful if special conditions are met.
Affected
14 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | samba | < samba 2:4.17.2+dfsg-3 (bookworm) | samba 2:4.17.2+dfsg-3 (bookworm) |
| fedoraproject | fedora | — | — |
| msrc | azl3_samba_4.18.3-1_on_azure_linux_3.0 | — | — |
| msrc | azure_linux_3.0_arm | — | — |
| msrc | azure_linux_3.0_x64 | — | — |
| samba | samba | — | — |
| samba | samba | >= 0 < 2:4.17.2+dfsg-3 | 2:4.17.2+dfsg-3 |
| samba | samba | >= 0 < 2:4.17.2+dfsg-3 | 2:4.17.2+dfsg-3 |
| samba | samba | >= 0 < 2:4.17.2+dfsg-3 | 2:4.17.2+dfsg-3 |
| samba | samba | >= 0 < 2:4.13.17~dfsg-0ubuntu1.20.04.5 | 2:4.13.17~dfsg-0ubuntu1.20.04.5 |
| samba | samba | >= 0 < 2:4.13.17~dfsg-0ubuntu1.20.04.4 | 2:4.13.17~dfsg-0ubuntu1.20.04.4 |
| samba | samba | >= 0 < 2:4.15.13+dfsg-0ubuntu1 | 2:4.15.13+dfsg-0ubuntu1 |
| samba | samba | >= 4.1.0 < 4.16.8 | 4.16.8 |
| samba | samba | >= 4.17.0 < 4.17.4 | 4.17.4 |
CVSS provenance
nvdv3.15.9MEDIUMCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
osv5.9MEDIUM
vendor_debian5.9MEDIUM
vendor_msrc5.9MEDIUM
vendor_redhat5.9MEDIUM
vendor_ubuntu5.9MEDIUM
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Microsoft
A flaw was found in samba. A race condition in the password lockout code may lead to the risk of brute force attacks being successful if special conditions are met.
vendor_msrc·2023-03-14·CVSS 5.9
CVE-2021-20251 [MEDIUM] CWE-362 A flaw was found in samba. A race condition in the password lockout code may lead to the risk of brute force attacks being successful if special conditions are met.
A flaw was found in samba. A race condition in the password lockout code may lead to the risk of brute force attacks being successful if special conditions are met.
FAQ: Is Azure Linux the only Microsoft product that includes this open-source library and is therefore potentially affected by this vulnerability?
One of the main benefits to our customers who choose to use the Azure Linux distro is the commitment to keep it up to date with the most recent and most secure versions of the open source libraries with which the distro is composed. Microsoft is committed to transparency in this work which is why we began publishing CSAF/VEX in October 2025. See this blog post for more information. If impact to additional products is identified, we will update the CVE to reflect this.
Mariner: Mari
Ubuntu
Samba regression
vendor_ubuntu·2023-01-26·CVSS 5.9
[MEDIUM] Samba regression
Title: Samba regression
Summary: USN 5822-1 introduced regressions on Ubuntu 20.04 LTS.
USN-5822-1 fixed vulnerabilities in Samba. The update for Ubuntu 20.04 LTS
introduced regressions in certain environments. Pending investigation of
these regressions, this update temporarily reverts the security fixes.
We apologize for the inconvenience.
Original advisory details:
It was discovered that Samba incorrectly handled the bad password count
logic. A remote attacker could possibly use this issue to bypass bad
passwords lockouts. This issue was only addressed in Ubuntu 22.10.
(CVE-2021-20251)
Evgeny Legerov discovered that Samba incorrectly handled buffers in
certain GSSAPI routines of Heimdal. A remote attacker could possibly use
this issue to cause Samba to crash, resulting in a denial
Ubuntu
Samba vulnerabilities
vendor_ubuntu·2023-01-24·CVSS 5.9
CVE-2022-37966 [MEDIUM] Samba vulnerabilities
Title: Samba vulnerabilities
Summary: Several security issues were fixed in Samba.
It was discovered that Samba incorrectly handled the bad password count
logic. A remote attacker could possibly use this issue to bypass bad
passwords lockouts. This issue was only addressed in Ubuntu 22.10.
(CVE-2021-20251)
Evgeny Legerov discovered that Samba incorrectly handled buffers in
certain GSSAPI routines of Heimdal. A remote attacker could possibly use
this issue to cause Samba to crash, resulting in a denial of service.
(CVE-2022-3437)
Tom Tervoort discovered that Samba incorrectly used weak rc4-hmac Kerberos
keys. A remote attacker could possibly use this issue to elevate
privileges. (CVE-2022-37966, CVE-2022-37967)
It was discovered that Samba supported weak RC4/HMAC-MD5 in NetLogon Secure
Red Hat
samba: Race condition in the bad password lockout code
vendor_redhat·2021-02-05·CVSS 5.9
CVE-2021-20251 [MEDIUM] CWE-362 samba: Race condition in the bad password lockout code
samba: Race condition in the bad password lockout code
A flaw was found in samba. A race condition in the password lockout code may lead to the risk of brute force attacks being successful if special conditions are met.
A flaw was found in samba. A race condition in the password lockout code may lead to the risk of brute force attacks being successful if special conditions are met.
Package: samba (Red Hat Enterprise Linux 6) - Not affected
Package: samba4 (Red Hat Enterprise Linux 6) - Not affected
Package: samba (Red Hat Enterprise Linux 7) - Not affected
Package: samba (Red Hat Enterprise Linux 8) - Not affected
Package: samba (Red Hat Enterprise Linux 9) - Not affected
Package: samba (Red Hat Storage 3) - Not affected
Debian
CVE-2021-20251: samba - A flaw was found in samba. A race condition in the password lockout code may lea...
vendor_debian·2021·CVSS 5.9
CVE-2021-20251 [MEDIUM] CVE-2021-20251: samba - A flaw was found in samba. A race condition in the password lockout code may lea...
A flaw was found in samba. A race condition in the password lockout code may lead to the risk of brute force attacks being successful if special conditions are met.
Scope: local
bookworm: resolved (fixed in 2:4.17.2+dfsg-3)
bullseye: open
forky: resolved (fixed in 2:4.17.2+dfsg-3)
sid: resolved (fixed in 2:4.17.2+dfsg-3)
trixie: resolved (fixed in 2:4.17.2+dfsg-3)
GHSA
GHSA-9ppx-3j9g-766w: A flaw was found in samba
ghsa_unreviewed·2023-03-07
CVE-2021-20251 [MEDIUM] CWE-362 GHSA-9ppx-3j9g-766w: A flaw was found in samba
A flaw was found in samba. A race condition in the password lockout code may lead to the risk of brute force attacks being successful if special conditions are met.
OSV
CVE-2021-20251: A flaw was found in samba
osv·2023-03-06·CVSS 5.9
CVE-2021-20251 [MEDIUM] CVE-2021-20251: A flaw was found in samba
A flaw was found in samba. A race condition in the password lockout code may lead to the risk of brute force attacks being successful if special conditions are met.
OSV
samba regression
osv·2023-01-26·CVSS 5.9
[MEDIUM] samba regression
samba regression
USN-5822-1 fixed vulnerabilities in Samba. The update for Ubuntu 20.04 LTS
introduced regressions in certain environments. Pending investigation of
these regressions, this update temporarily reverts the security fixes.
We apologize for the inconvenience.
Original advisory details:
It was discovered that Samba incorrectly handled the bad password count
logic. A remote attacker could possibly use this issue to bypass bad
passwords lockouts. This issue was only addressed in Ubuntu 22.10.
(CVE-2021-20251)
Evgeny Legerov discovered that Samba incorrectly handled buffers in
certain GSSAPI routines of Heimdal. A remote attacker could possibly use
this issue to cause Samba to crash, resulting in a denial of service.
(CVE-2022-3437)
Tom Tervoort discovered that Samba incorrec
OSV
samba vulnerabilities
osv·2023-01-24·CVSS 5.9
CVE-2021-20251 [MEDIUM] samba vulnerabilities
samba vulnerabilities
It was discovered that Samba incorrectly handled the bad password count
logic. A remote attacker could possibly use this issue to bypass bad
passwords lockouts. This issue was only addressed in Ubuntu 22.10.
(CVE-2021-20251)
Evgeny Legerov discovered that Samba incorrectly handled buffers in
certain GSSAPI routines of Heimdal. A remote attacker could possibly use
this issue to cause Samba to crash, resulting in a denial of service.
(CVE-2022-3437)
Tom Tervoort discovered that Samba incorrectly used weak rc4-hmac Kerberos
keys. A remote attacker could possibly use this issue to elevate
privileges. (CVE-2022-37966, CVE-2022-37967)
It was discovered that Samba supported weak RC4/HMAC-MD5 in NetLogon Secure
Channel. A remote attacker could possibly use this issue to e
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
https://bugzilla.redhat.com/show_bug.cgi?id=1929800https://bugzilla.samba.org/show_bug.cgi?id=14611https://security.gentoo.org/glsa/202309-06https://security.netapp.com/advisory/ntap-20230331-0005/https://bugzilla.redhat.com/show_bug.cgi?id=1929800https://bugzilla.samba.org/show_bug.cgi?id=14611https://security.gentoo.org/glsa/202309-06https://security.netapp.com/advisory/ntap-20230331-0005/
2023-03-06
Published