Vulnerability · Published Jun 22, 2023 · Assigned by GitHub_M
CVE-2023-34241CUPS vulnerable to use-after-free in cupsdAcceptClient()
Medium 5.3
In plain English
A medium-severity use-after-free in cups from OpenPrinting. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 1.4% (higher than 72% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux:8 | cups | 1:2.2.6-54.el8_9 | ALSA-2023:7165 |
| AlmaLinux:9 | cups | 1:2.3.3op2-21.el9 | ALSA-2023:6596 |
| AlmaLinux:8 | cups-client | 1:2.2.6-54.el8_9 | ALSA-2023:7165 |
| AlmaLinux:9 | cups-client | 1:2.3.3op2-21.el9 | ALSA-2023:6596 |
| AlmaLinux:8 | cups-devel | 1:2.2.6-54.el8_9 | ALSA-2023:7165 |
| AlmaLinux:9 | cups-devel | 1:2.3.3op2-21.el9 | ALSA-2023:6596 |
| AlmaLinux:8 | cups-filesystem | 1:2.2.6-54.el8_9 | ALSA-2023:7165 |
| AlmaLinux:9 | cups-filesystem | 1:2.3.3op2-21.el9 | ALSA-2023:6596 |
| AlmaLinux:8 | cups-ipptool | 1:2.2.6-54.el8_9 | ALSA-2023:7165 |
| AlmaLinux:9 | cups-ipptool | 1:2.3.3op2-21.el9 | ALSA-2023:6596 |
| AlmaLinux:8 | cups-libs | 1:2.2.6-54.el8_9 | ALSA-2023:7165 |
| AlmaLinux:9 | cups-libs | 1:2.3.3op2-21.el9 | ALSA-2023:6596 |
| AlmaLinux:8 | cups-lpd | 1:2.2.6-54.el8_9 | ALSA-2023:7165 |
| AlmaLinux:9 | cups-lpd | 1:2.3.3op2-21.el9 | ALSA-2023:6596 |
| AlmaLinux:9 | cups-printerapp | 1:2.3.3op2-21.el9 | ALSA-2023:6596 |
| Debian:12 | cups | 2.4.2-3+deb12u1 | DEBIAN-CVE-2023-34241 |
| Debian:13 | cups | 2.4.2-5 | DEBIAN-CVE-2023-34241 |
| Debian:14 | cups | 2.4.2-5 | DEBIAN-CVE-2023-34241 |
| Ubuntu:22.04:LTS | cups | 2.4.1op1-1ubuntu4.4 | USN-6184-1 |
| Ubuntu:22.04:LTS | cups | 2.4.1op1-1ubuntu4.4 | UBUNTU-CVE-2023-34241 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| OpenPrinting | cups | >= 2.0.0, < 2.4.6 |
Weakness: CWE-416 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
References
- https://github.com/OpenPrinting/cups/security/advisories/GHSA-qjgh-5hcq-5f25 x_refsource_CONFIRM
- https://github.com/OpenPrinting/cups/commit/9809947a959e18409dcf562a3466ef246cb90cb2 x_refsource_MISC
- https://github.com/OpenPrinting/cups/releases/tag/v2.4.6 x_refsource_MISC
- http://www.openwall.com/lists/oss-security/2023/06/23/10
- http://www.openwall.com/lists/oss-security/2023/06/26/1
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/TBIYKDS3UG3W4Z7YOHTR2AWFNBRYPNYY/
- https://lists.debian.org/debian-lts-announce/2023/06/msg00038.html
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/7I7DWGYGEMBNLZF5UQBMF3SONR37YUBN/
- https://support.apple.com/kb/HT213843
- https://support.apple.com/kb/HT213844
- https://support.apple.com/kb/HT213845