// For flags

CVE-2023-34241

CUPS vulnerable to use-after-free in cupsdAcceptClient()

Severity Score

7.1
*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

1
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

-
*SSVC
Descriptions

OpenPrinting CUPS is a standards-based, open source printing system for Linux and other Unix-like operating systems. Starting in version 2.0.0 and prior to version 2.4.6, CUPS logs data of free memory to the logging service AFTER the connection has been closed, when it should have logged the data right before. This is a use-after-free bug that impacts the entire cupsd process.

The exact cause of this issue is the function `httpClose(con->http)` being called in `scheduler/client.c`. The problem is that httpClose always, provided its argument is not null, frees the pointer at the end of the call, only for cupsdLogClient to pass the pointer to httpGetHostname. This issue happens in function `cupsdAcceptClient` if LogLevel is warn or higher and in two scenarios: there is a double-lookup for the IP Address (HostNameLookups Double is set in `cupsd.conf`) which fails to resolve, or if CUPS is compiled with TCP wrappers and the connection is refused by rules from `/etc/hosts.allow` and `/etc/hosts.deny`.

Version 2.4.6 has a patch for this issue.

A vulnerability was found in CUPS. This issue occurs due to logging data of free memory to the logging service AFTER the connection has been closed, when it should have logged the data immediately before the connection closed, resulting in a use-after-free in cupsdAcceptClient() in scheduler/client.c

*Credits: N/A
CVSS Scores
Attack Vector
Local
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
None
Availability
High
Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
Low
* Common Vulnerability Scoring System
SSVC
  • Decision:-
Exploitation
-
Automatable
-
Tech. Impact
-
* Organization's Worst-case Scenario
Timeline
  • 2023-05-31 CVE Reserved
  • 2023-06-22 CVE Published
  • 2024-08-02 CVE Updated
  • 2024-08-02 First Exploit
  • 2024-09-26 EPSS Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
CWE
  • CWE-416: Use After Free
CAPEC
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
Openprinting
Search vendor "Openprinting"
 Cups
Search vendor "Openprinting" for product "Cups"
 >= 2.2.0 < 2.4.6
Search vendor "Openprinting" for product "Cups" and version " >= 2.2.0 < 2.4.6"
-
Affected
Fedoraproject
Search vendor "Fedoraproject"
 Fedora
Search vendor "Fedoraproject" for product "Fedora"
 37
Search vendor "Fedoraproject" for product "Fedora" and version "37"
-
Affected
Fedoraproject
Search vendor "Fedoraproject"
 Fedora
Search vendor "Fedoraproject" for product "Fedora"
 38
Search vendor "Fedoraproject" for product "Fedora" and version "38"
-
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
Apple
Search vendor "Apple"
 Macos
Search vendor "Apple" for product "Macos"
 < 11.7.9
Search vendor "Apple" for product "Macos" and version " < 11.7.9"
-
Affected
Apple
Search vendor "Apple"
 Macos
Search vendor "Apple" for product "Macos"
 >= 12.0.0 < 12.6.8
Search vendor "Apple" for product "Macos" and version " >= 12.0.0 < 12.6.8"
-
Affected
Apple
Search vendor "Apple"
 Macos
Search vendor "Apple" for product "Macos"
 >= 13.0 < 13.5
Search vendor "Apple" for product "Macos" and version " >= 13.0 < 13.5"
-
Affected