Headline
CVE-2023-1393: security - Fwd: X.Org Security Advisory: CVE-2023-1393: X.Org Server Overlay Window Use-After-Free
A flaw was found in X.Org Server Overlay Window. A Use-After-Free may lead to local privilege escalation. If a client explicitly destroys the compositor overlay window (aka COW), the Xserver would leave a dangling pointer to that window in the CompScreen structure, which will trigger a use-after-free later.
- Products
- Openwall GNU/*/Linux server OS
- Linux Kernel Runtime Guard
- John the Ripper password cracker
- Free & Open Source for any platform
- in the cloud
- Pro for Linux
- Pro for macOS
- Wordlists for password cracking
- passwdqc policy enforcement
- Free & Open Source for Unix
- Pro for Windows (Active Directory)
- yescrypt KDF & password hashing
- yespower Proof-of-Work (PoW)
- crypt_blowfish password hashing
- phpass ditto in PHP
- tcb better password shadowing
- Pluggable Authentication Modules
- scanlogd port scan detector
- popa3d tiny POP3 daemon
- blists web interface to mailing lists
- msulogin single user mode login
- php_mt_seed mt_rand() cracker
- Services
- Publications
- Articles
- Presentations
- Resources
- Mailing lists
- Community wiki
- Source code repositories (GitHub)
- Source code repositories (CVSweb)
- File archive & mirrors
- How to verify digital signatures
- OVE IDs
- What’s new
[<prev] [next>] [day] [month] [year] [list]
Date: Wed, 29 Mar 2023 14:31:54 +0200 From: Olivier Fourdan <ofourdan@…hat.com> To: oss-security@…ts.openwall.com Subject: Fwd: X.Org Security Advisory: CVE-2023-1393: X.Org Server Overlay Window Use-After-Free
-------- Forwarded Message -------- Subject: X.Org Security Advisory: CVE-2023-1393: X.Org Server Overlay Window Use-After-Free Date: Wed, 29 Mar 2023 14:15:05 +0200 From: Olivier Fourdan <ofourdan@…hat.com> To: xorg-announce@…ts.x.org CC: xorg@…ts.x.org, xorg-devel <xorg-devel@…ts.x.org>, zdi-disclosures@…ndmicro.com
X.Org Security Advisory: March 29, 2023
X.Org Server Overlay Window Use-After-Free
This issue can lead to local privileges elevation on systems where the X server is running privileged and remote code execution for ssh X forwarding sessions.
ZDI-CAN-19866/CVE-2023-1393: X.Org Server Overlay Window Use-After-Free Local Privilege Escalation Vulnerability
If a client explicitly destroys the compositor overlay window (aka COW), the Xserver would leave a dangling pointer to that window in the CompScreen structure, which will trigger a use-after-free later.
Patches
Patch for this issue have been committed to the xorg server git repository. xorg-server 21.1.8 will be released shortly and will include this patch.
- commit 26ef545b3 - composite: Fix use-after-free of the COW (https://gitlab.freedesktop.org/xorg/xserver/-/commit/26ef545b3)
ZDI-CAN-19866/CVE-2023-1393
If a client explicitly destroys the compositor overlay window (aka COW), we would leave a dangling pointer to that window in the CompScreen structure, which will trigger a use-after-free later.
Make sure to clear the CompScreen pointer to the COW when the latter gets destroyed explicitly by the client.
Thanks
The vulnerabilities have been discovered by Jan-Niklas Sohn working with Trend Micro Zero Day Initiative. Download attachment "OpenPGP_0x14706DBE1E4B4540.asc" of type "application/pgp-keys" (2990 bytes)
Powered by blists - more mailing lists
Please check out the Open Source Software Security Wiki, which is counterpart to this mailing list.
Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.
Related news
Red Hat Security Advisory 2023-1600-01 - Virtual Network Computing is a remote display system which allows users to view a computing desktop environment not only on the machine where it is running, but from anywhere on the Internet and from a wide variety of machine architectures. TigerVNC is a suite of VNC servers and clients. Issues addressed include privilege escalation and use-after-free vulnerabilities.
Red Hat Security Advisory 2023-1594-01 - Virtual Network Computing is a remote display system which allows users to view a computing desktop environment not only on the machine where it is running, but from anywhere on the Internet and from a wide variety of machine architectures. TigerVNC is a suite of VNC servers and clients. X.Org is an open-source implementation of the X Window System. It provides the basic low-level functionality that full-fledged graphical user interfaces are designed upon. Issues addressed include privilege escalation and use-after-free vulnerabilities.
An update for tigervnc and xorg-x11-server is now available for Red Hat Enterprise Linux 7. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Red Hat Inc. and provide a link to the original. Related CVEs: * CVE-2023-1393: A flaw was found in X.Org Server Overlay Window. A Use-After-Free may lead to local privilege escalation. If a client explicitly destroys the compositor overlay window (aka COW), the Xserver would leave a dangling pointer to that window in the CompScreen structure, which will trigger a use-after-free later.
An update for tigervnc is now available for Red Hat Enterprise Linux 8.6 Extended Update Support. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Red Hat Inc. and provide a link to the original. Related CVEs: * CVE-2023-1393: A flaw was found in X.Org Server Overlay Window. A Use-After-Free may lead to local privilege escalation. If a client explicitly destroys the compositor overlay window (aka COW), the Xserver would leave a dangling pointer to that window in the CompScreen structure, which will trigger a use-after-free later.
An update for tigervnc is now available for Red Hat Enterprise Linux 9.0 Extended Update Support. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Red Hat Inc. and provide a link to the original. Related CVEs: * CVE-2023-1393: A flaw was found in X.Org Server Overlay Window. A Use-After-Free may lead to local privilege escalation. If a client explicitly destroys the compositor overlay window (aka COW), the Xserver would leave a dangling pointer to that window in the CompScreen structure, which will trigger a use-after-free later.
An update for tigervnc is now available for Red Hat Enterprise Linux 8.1 Update Services for SAP Solutions. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Red Hat Inc. and provide a link to the original. Related CVEs: * CVE-2023-1393: A flaw was found in X.Org Server Overlay Window. A Use-After-Free may lead to local privilege escalation. If a client explicitly destroys the compositor overlay window (aka COW), the Xserver would leave a dangling pointer to that window in the CompScreen structure, which will trigger a use-after-free later.
An update for tigervnc is now available for Red Hat Enterprise Linux 9. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Red Hat Inc. and provide a link to the original. Related CVEs: * CVE-2023-1393: A flaw was found in X.Org Server Overlay Window. A Use-After-Free may lead to local privilege escalation. If a client explicitly destroys the compositor overlay window (aka COW), the Xserver would leave a dangling pointer to that window in the CompScreen structure, which will trigger a use-after-free later.
An update for tigervnc is now available for Red Hat Enterprise Linux 8. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Red Hat Inc. and provide a link to the original. Related CVEs: * CVE-2023-1393: A flaw was found in X.Org Server Overlay Window. A Use-After-Free may lead to local privilege escalation. If a client explicitly destroys the compositor overlay window (aka COW), the Xserver would leave a dangling pointer to that window in the CompScreen structure, which will trigger a use-after-free later.
An update for tigervnc is now available for Red Hat Enterprise Linux 8.4 Extended Update Support. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Red Hat Inc. and provide a link to the original. Related CVEs: * CVE-2023-1393: A flaw was found in X.Org Server Overlay Window. A Use-After-Free may lead to local privilege escalation. If a client explicitly destroys the compositor overlay window (aka COW), the Xserver would leave a dangling pointer to that window in the CompScreen structure, which will trigger a use-after-free later.
Ubuntu Security Notice 5986-1 - Jan-Niklas Sohn discovered that the X.Org X Server incorrectly handled certain memory operations. An attacker could possibly use these issues to cause the X Server to crash, execute arbitrary code, or escalate privileges.
Debian Linux Security Advisory 5380-1 - Jan-Niklas Sohn discovered that a user-after-free flaw in the Composite extension of the X.org X server may result in privilege escalation if the X server is running under the root user.