CVE-2020-27840
published 2021-05-12CVE-2020-27840: A flaw was found in samba. Spaces used in a string around a domain name (DN), while supposed to be ignored, can cause invalid DN strings with spaces to instead…
PriorityP340high7.5CVSS 3.1
AVNACLPRNUINSUCNINAH
EPSS
3.83%
88.9th percentile
A flaw was found in samba. Spaces used in a string around a domain name (DN), while supposed to be ignored, can cause invalid DN strings with spaces to instead write a zero-byte into out-of-bounds memory, resulting in a crash. The highest threat from this vulnerability is to system availability.
Affected
19 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | debian_linux | — | — |
| debian | debian_linux | — | — |
| debian | ldb | < ldb 2:2.2.0-3.1 (bullseye) | ldb 2:2.2.0-3.1 (bullseye) |
| debian | samba | < ldb 2:2.2.0-3.1 (bullseye) | ldb 2:2.2.0-3.1 (bullseye) |
| fedoraproject | fedora | — | — |
| fedoraproject | fedora | — | — |
| fedoraproject | fedora | — | — |
| msrc | azl3_libldb_2.7.2-1_on_azure_linux_3.0 | — | — |
| msrc | azl3_samba_4.18.3-1_on_azure_linux_3.0 | — | — |
| msrc | azure_linux_3.0_arm | — | — |
| msrc | azure_linux_3.0_x64 | — | — |
| msrc | cbl2_samba_4.12.5-6_on_cbl_mariner_2.0 | — | — |
| samba | samba | — | — |
| samba | samba | >= 0 < 2:4.13.13+dfsg-1 | 2:4.13.13+dfsg-1 |
| samba | samba | >= 0 < 2:4.13.13+dfsg-1 | 2:4.13.13+dfsg-1 |
| samba | samba | >= 0 < 2:4.13.13+dfsg-1 | 2:4.13.13+dfsg-1 |
| samba | samba | >= 4.0.0 < 4.12.13 | 4.12.13 |
| samba | samba | >= 4.13.0 < 4.13.6 | 4.13.6 |
| samba | samba | >= 4.14.0 < 4.14.1 | 4.14.1 |
CVSS provenance
nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
nvdv2.05.0MEDIUMAV:N/AC:L/Au:N/C:N/I:N/A:P
osv7.5HIGH
vendor_debian7.5HIGH
vendor_msrc7.5HIGH
vendor_redhat7.5HIGH
vendor_ubuntu7.5HIGH
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Microsoft
A flaw was found in samba. Spaces used in a string around a domain name (DN) while supposed to be ignored can cause invalid DN strings with spaces to instead write a zero-byte into out-of-bounds memor
vendor_msrc·2021-05-11·CVSS 7.5
CVE-2020-27840 [HIGH] CWE-125 A flaw was found in samba. Spaces used in a string around a domain name (DN) while supposed to be ignored can cause invalid DN strings with spaces to instead write a zero-byte into out-of-bounds memor
A flaw was found in samba. Spaces used in a string around a domain name (DN) while supposed to be ignored can cause invalid DN strings with spaces to instead write a zero-byte into out-of-bounds memory resulting in a crash. The highest threat from this vulnerability is to system availability.
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
Ubuntu
ldb vulnerabilities
vendor_ubuntu·2021-03-25·CVSS 7.5
CVE-2020-27840 [HIGH] ldb vulnerabilities
Title: ldb vulnerabilities
Summary: Several security issues were fixed in ldb.
USN-4888-1 fixed several vulnerabilities in ldb. This update provides
the corresponding update for Ubuntu 14.04 ESM.
Original advisory details:
Douglas Bagnall discovered that ldb, when used with Samba, incorrectly
handled certain LDAP attributes. A remote attacker could possibly use this
issue to cause the LDAP server to crash, resulting in a denial of service.
(CVE-2021-20277)
Douglas Bagnall discovered that ldb, when used with Samba, incorrectly
handled certain DN strings. A remote attacker could use this issue to
cause the LDAP server to crash, resulting in a denial of service, or
possibly execute arbitrary code. (CVE-2020-27840)
Instructions: After a standard system update you need to restart applicat
Red Hat
samba: Heap corruption via crafted DN strings
vendor_redhat·2021-03-24·CVSS 7.5
CVE-2020-27840 [HIGH] CWE-125 samba: Heap corruption via crafted DN strings
samba: Heap corruption via crafted DN strings
A flaw was found in samba. Spaces used in a string around a domain name (DN), while supposed to be ignored, can cause invalid DN strings with spaces to instead write a zero-byte into out-of-bounds memory, resulting in a crash. The highest threat from this vulnerability is to system availability.
A flaw was found in samba. Spaces used in a string around a domain name (DN), while supposed to be ignored, can cause invalid DN strings with spaces to instead write a zero-byte into out-of-bounds memory, resulting in a crash. The highest threat from this vulnerability is to system availability.
Statement: This flaw does not affect the version of Samba shipped with Red Hat Enterprise Linux and Red Hat Gluster Storage 3 because there is no support for
Ubuntu
ldb vulnerabilities
vendor_ubuntu·2021-03-24·CVSS 7.5
CVE-2021-20277 [HIGH] ldb vulnerabilities
Title: ldb vulnerabilities
Summary: Several security issues were fixed in ldb.
Douglas Bagnall discovered that ldb, when used with Samba, incorrectly
handled certain LDAP attributes. A remote attacker could possibly use this
issue to cause the LDAP server to crash, resulting in a denial of service.
(CVE-2021-20277)
Douglas Bagnall discovered that ldb, when used with Samba, incorrectly
handled certain DN strings. A remote attacker could use this issue to
cause the LDAP server to crash, resulting in a denial of service, or
possibly execute arbitrary code. (CVE-2020-27840)
Instructions: After a standard system update you need to restart applications using ldb,
such as Samba, to make all the necessary changes.
Debian
CVE-2020-27840: ldb - A flaw was found in samba. Spaces used in a string around a domain name (DN), wh...
vendor_debian·2020·CVSS 7.5
CVE-2020-27840 [HIGH] CVE-2020-27840: ldb - A flaw was found in samba. Spaces used in a string around a domain name (DN), wh...
A flaw was found in samba. Spaces used in a string around a domain name (DN), while supposed to be ignored, can cause invalid DN strings with spaces to instead write a zero-byte into out-of-bounds memory, resulting in a crash. The highest threat from this vulnerability is to system availability.
Scope: local
bullseye: resolved (fixed in 2:2.2.0-3.1)
GHSA
GHSA-36xh-w73j-574g: A flaw was found in samba
ghsa_unreviewed·2022-05-24
CVE-2020-27840 [HIGH] CWE-125 GHSA-36xh-w73j-574g: A flaw was found in samba
A flaw was found in samba. Spaces used in a string around a domain name (DN), while supposed to be ignored, can cause invalid DN strings with spaces to instead write a zero-byte into out-of-bounds memory, resulting in a crash. The highest threat from this vulnerability is to system availability.
OSV
CVE-2020-27840: A flaw was found in samba
osv·2021-05-12·CVSS 7.5
CVE-2020-27840 [HIGH] CVE-2020-27840: A flaw was found in samba
A flaw was found in samba. Spaces used in a string around a domain name (DN), while supposed to be ignored, can cause invalid DN strings with spaces to instead write a zero-byte into out-of-bounds memory, resulting in a crash. The highest threat from this vulnerability is to system availability.
OSV
ldb vulnerabilities
osv·2021-03-25·CVSS 7.5
CVE-2021-20277 [HIGH] ldb vulnerabilities
ldb vulnerabilities
USN-4888-1 fixed several vulnerabilities in ldb. This update provides
the corresponding update for Ubuntu 14.04 ESM.
Original advisory details:
Douglas Bagnall discovered that ldb, when used with Samba, incorrectly
handled certain LDAP attributes. A remote attacker could possibly use this
issue to cause the LDAP server to crash, resulting in a denial of service.
(CVE-2021-20277)
Douglas Bagnall discovered that ldb, when used with Samba, incorrectly
handled certain DN strings. A remote attacker could use this issue to
cause the LDAP server to crash, resulting in a denial of service, or
possibly execute arbitrary code. (CVE-2020-27840)
OSV
ldb vulnerabilities
osv·2021-03-24·CVSS 7.5
CVE-2021-20277 [HIGH] ldb vulnerabilities
ldb vulnerabilities
Douglas Bagnall discovered that ldb, when used with Samba, incorrectly
handled certain LDAP attributes. A remote attacker could possibly use this
issue to cause the LDAP server to crash, resulting in a denial of service.
(CVE-2021-20277)
Douglas Bagnall discovered that ldb, when used with Samba, incorrectly
handled certain DN strings. A remote attacker could use this issue to
cause the LDAP server to crash, resulting in a denial of service, or
possibly execute arbitrary code. (CVE-2020-27840)
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
https://bugzilla.redhat.com/show_bug.cgi?id=1941400https://lists.debian.org/debian-lts-announce/2021/03/msg00036.htmlhttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VLZ74IF2N75VQSIHBL4B3P5WKWQCXSRY/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/X5J3B6PN5XMXF3OHYBNHDKZ3XFSUGY4L/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZXP3ONIY6MB4C5LDZV4YL5KJCES3UX24/https://security.gentoo.org/glsa/202105-22https://security.netapp.com/advisory/ntap-20210326-0007/https://www.debian.org/security/2021/dsa-4884https://www.samba.org/samba/security/CVE-2020-27840.htmlhttps://bugzilla.redhat.com/show_bug.cgi?id=1941400https://lists.debian.org/debian-lts-announce/2021/03/msg00036.htmlhttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VLZ74IF2N75VQSIHBL4B3P5WKWQCXSRY/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/X5J3B6PN5XMXF3OHYBNHDKZ3XFSUGY4L/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZXP3ONIY6MB4C5LDZV4YL5KJCES3UX24/https://security.gentoo.org/glsa/202105-22https://security.netapp.com/advisory/ntap-20210326-0007/https://www.debian.org/security/2021/dsa-4884https://www.samba.org/samba/security/CVE-2020-27840.html
2021-05-12
Published