Bug 934750 (CVE-2024-35235)

Summary:	<net-print/cups-2.4.10: Listen symbol link privilege escalation vulnerability
Product:	Gentoo Security	Reporter:	Sam James <sam>
Component:	Vulnerabilities	Assignee:	Gentoo Security <security>
Status:	IN_PROGRESS ---
Severity:	normal	CC:	kripton, printing
Priority:	Normal
Version:	unspecified
Hardware:	All
OS:	Linux
Whiteboard:	B2 [cleanup glsa?]
Package list:		Runtime testing required:	---
Bug Depends on:	940015, 942429
Bug Blocks:

Description Sam James archtester

2024-06-23 00:18:27 UTC

"OpenPrinting CUPS is an open source printing system for Linux and other Unix-like operating systems.

In versions 2.4.8 and earlier, when starting the cupsd server with a Listen configuration item pointing to a symbolic link, the cupsd process can be caused to perform an arbitrary chmod of the provided argument, providing world-writable access to the target. Given that cupsd is often running as root, this can result in the change of permission of any user or system files to be world writable. Given the aforementioned Ubuntu AppArmor context, on such systems this vulnerability is limited to those files modifiable by the cupsd process.

In that specific case it was found to be possible to turn the configuration of the Listen argument into full control over the cupsd.conf and cups-files.conf configuration files. By later setting the User and Group arguments in cups-files.conf, and printing with a printer configured by PPD with a `FoomaticRIPCommandLine` argument, arbitrary user and group (not root) command execution could be achieved, which can further be used on Ubuntu systems to achieve full root command execution. Commit ff1f8a623e090dee8a8aadf12a6a4b25efac143d contains a patch for the issue."

Comment 1 Larry the Git Cow gentoo-dev

2024-06-23 00:27:39 UTC

The bug has been referenced in the following commit(s):

https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=1834c0a3f57762042870033743977e609a73d4eb

commit 1834c0a3f57762042870033743977e609a73d4eb
Author:     Sam James <sam@gentoo.org>
AuthorDate: 2024-06-23 00:25:35 +0000
Commit:     Sam James <sam@gentoo.org>
CommitDate: 2024-06-23 00:27:09 +0000

    net-print/cups: add 2.4.10
    
    Bug: https://bugs.gentoo.org/934750
    Signed-off-by: Sam James <sam@gentoo.org>

 net-print/cups/Manifest           |   1 +
 net-print/cups/cups-2.4.10.ebuild | 320 ++++++++++++++++++++++++++++++++++++++
 net-print/cups/cups-9999.ebuild   |  10 +-
 3 files changed, 326 insertions(+), 5 deletions(-)