// For flags

CVE-2009-2906

samba: infinite loop flaw in smbd on unexpected oplock break notification reply

Severity Score

6.5
*CVSS v3

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

0
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

-
*SSVC
Descriptions

smbd in Samba 3.0 before 3.0.37, 3.2 before 3.2.15, 3.3 before 3.3.8, and 3.4 before 3.4.2 allows remote authenticated users to cause a denial of service (infinite loop) via an unanticipated oplock break notification reply packet.

smbd en Samba v3.0 anterior a v3.0.37, v3.2 anterior a v3.2.15, v3.3 anterior a v3.3.8 y v3.4 anterior a v3.4.2, permite a usuarios autenticados remotamente provocar una denegación de servicio (bucle infinito) a través de un paquete de notificación de respuesta "oplock break" imprevisto.

J. David Hester discovered that Samba incorrectly handled users that lack home directories when the automated [homes] share is enabled. An authenticated user could connect to that share name and gain access to the whole filesystem. Tim Prouty discovered that the smbd daemon in Samba incorrectly handled certain unexpected network replies. A remote attacker could send malicious replies to the server and cause smbd to use all available CPU, leading to a denial of service. Ronald Volgers discovered that the mount.cifs utility, when installed as a setuid program, would not verify user permissions before opening a credentials file. A local user could exploit this to use or read the contents of unauthorized credential files. Reinhard discovered that the smbclient utility contained format string vulnerabilities in its file name handling. Because of security features in Ubuntu, exploitation of this vulnerability is limited. If a user or automated system were tricked into processing a specially crafted file name, smbclient could be made to crash, possibly leading to a denial of service. This only affected Ubuntu 8.10. Jeremy Allison discovered that the smbd daemon in Samba incorrectly handled permissions to modify access control lists when dos filemode is enabled. A remote attacker could exploit this to modify access control lists. This only affected Ubuntu 8.10 and Ubuntu 9.04.

*Credits: N/A
CVSS Scores
Attack Vector
Network
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
Attack Vector
Network
Attack Complexity
Low
Authentication
Single
Confidentiality
None
Integrity
None
Availability
Partial
Attack Vector
Adjacent
Attack Complexity
Medium
Authentication
Single
Confidentiality
None
Integrity
None
Availability
Partial
* Common Vulnerability Scoring System
SSVC
  • Decision:-
Exploitation
-
Automatable
-
Tech. Impact
-
* Organization's Worst-case Scenario
Timeline
  • 2009-08-20 CVE Reserved
  • 2009-10-02 CVE Published
  • 2024-08-07 CVE Updated
  • 2025-06-23 EPSS Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
  • CWE-835: Loop with Unreachable Exit Condition ('Infinite Loop')
CAPEC
References (29)
URL Date SRC
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"
< 3.0.37
Search vendor "Samba" for product "Samba" and version " < 3.0.37"
-
Affected
Samba
Search vendor "Samba"
Samba
Search vendor "Samba" for product "Samba"
>= 3.2.0 < 3.2.15
Search vendor "Samba" for product "Samba" and version " >= 3.2.0 < 3.2.15"
-
Affected
Samba
Search vendor "Samba"
Samba
Search vendor "Samba" for product "Samba"
>= 3.3.0 < 3.3.8
Search vendor "Samba" for product "Samba" and version " >= 3.3.0 < 3.3.8"
-
Affected
Samba
Search vendor "Samba"
Samba
Search vendor "Samba" for product "Samba"
3.4.0
Search vendor "Samba" for product "Samba" and version "3.4.0"
-
Affected
Samba
Search vendor "Samba"
Samba
Search vendor "Samba" for product "Samba"
3.4.1
Search vendor "Samba" for product "Samba" and version "3.4.1"
-
Affected
Canonical
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Ubuntu Linux
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6.06
Search vendor "Canonical" for product "Ubuntu Linux" and version "6.06"
-
Affected
Canonical
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Ubuntu Linux
Search vendor "Canonical" for product "Ubuntu Linux"
8.04
Search vendor "Canonical" for product "Ubuntu Linux" and version "8.04"
-
Affected
Canonical
Search vendor "Canonical"
Ubuntu Linux
Search vendor "Canonical" for product "Ubuntu Linux"
8.10
Search vendor "Canonical" for product "Ubuntu Linux" and version "8.10"
-
Affected
Canonical
Search vendor "Canonical"
Ubuntu Linux
Search vendor "Canonical" for product "Ubuntu Linux"
9.04
Search vendor "Canonical" for product "Ubuntu Linux" and version "9.04"
-
Affected