// For flags

CVE-2021-20277

samba: Out of bounds read in AD DC LDAP server

Severity Score

7.5
*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

0
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

-
*SSVC
Descriptions

A flaw was found in Samba's libldb. Multiple, consecutive leading spaces in an LDAP attribute can lead to an out-of-bounds memory write, leading to a crash of the LDAP server process handling the request. The highest threat from this vulnerability is to system availability.

Se encontró un fallo en libldb de Samba. Múltiples espacios iniciales consecutivos en un atributo LDAP pueden conllevar a una escritura de memoria fuera de los límites, conllevando a un bloqueo del proceso del servidor LDAP que maneja la petición. La mayor amenaza de esta vulnerabilidad es la disponibilidad del sistema

USN-4888-1 fixed several vulnerabilities in ldb. This update provides the corresponding update for Ubuntu 14.04 ESM. 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. 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. Various other issues were also addressed.

*Credits: N/A
CVSS Scores
Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
Attack Vector
Network
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
None
Availability
High
Attack Vector
Network
Attack Complexity
Low
Authentication
None
Confidentiality
None
Integrity
None
Availability
Partial
* Common Vulnerability Scoring System
SSVC
  • Decision:-
Exploitation
-
Automatable
-
Tech. Impact
-
* Organization's Worst-case Scenario
Timeline
  • 2020-12-17 CVE Reserved
  • 2021-03-25 CVE Published
  • 2024-08-03 CVE Updated
  • 2025-03-30 EPSS Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
  • CWE-125: Out-of-bounds Read
  • CWE-787: Out-of-bounds Write
CAPEC
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
Samba
Search vendor "Samba"
 Samba
Search vendor "Samba" for product "Samba"
 >= 4.0.0 < 4.12.13
Search vendor "Samba" for product "Samba" and version " >= 4.0.0 < 4.12.13"
-
Affected
Samba
Search vendor "Samba"
 Samba
Search vendor "Samba" for product "Samba"
 >= 4.13.0 < 4.13.6
Search vendor "Samba" for product "Samba" and version " >= 4.13.0 < 4.13.6"
-
Affected
Samba
Search vendor "Samba"
 Samba
Search vendor "Samba" for product "Samba"
 >= 4.14.0 < 4.14.1
Search vendor "Samba" for product "Samba" and version " >= 4.14.0 < 4.14.1"
-
Affected
Debian
Search vendor "Debian"
 Debian Linux
Search vendor "Debian" for product "Debian Linux"
 9.0
Search vendor "Debian" for product "Debian Linux" and version "9.0"
-
Affected
Debian
Search vendor "Debian"
 Debian Linux
Search vendor "Debian" for product "Debian Linux"
 10.0
Search vendor "Debian" for product "Debian Linux" and version "10.0"
-
Affected
Fedoraproject
Search vendor "Fedoraproject"
 Fedora
Search vendor "Fedoraproject" for product "Fedora"
 32
Search vendor "Fedoraproject" for product "Fedora" and version "32"
-
Affected
Fedoraproject
Search vendor "Fedoraproject"
 Fedora
Search vendor "Fedoraproject" for product "Fedora"
 33
Search vendor "Fedoraproject" for product "Fedora" and version "33"
-
Affected
Fedoraproject
Search vendor "Fedoraproject"
 Fedora
Search vendor "Fedoraproject" for product "Fedora"
 34
Search vendor "Fedoraproject" for product "Fedora" and version "34"
-
Affected