Bug 2494191 (CVE-2026-11979) - CVE-2026-11979 libxml2: libxml2: Arbitrary code execution in xmlcatalog utility via buffer overflow
Summary: CVE-2026-11979 libxml2: libxml2: Arbitrary code execution in xmlcatalog utili...
Keywords:
Status: NEW
Alias: CVE-2026-11979
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
medium
medium
Target Milestone: ---
Assignee: Product Security
QA Contact:
URL:
Whiteboard:
Depends On: 2494690 2494691 2494692 2494694 2494696 2494693 2494695
Blocks:
TreeView+ depends on / blocked
 
Reported: 2026-06-29 14:01 UTC by OSIDB Bzimport
Modified: 2026-11-02 03:33 UTC (History)
28 users (show)

Fixed In Version:
Clone Of:
Environment:
Last Closed:
Embargoed:

Attachments (Terms of Use)


Links
System ID Private Priority Status Summary Last Updated
Red Hat Product Errata RHBA-2026:61499 0 None None None 2026-08-31 12:14:34 UTC
Red Hat Product Errata RHBA-2026:61500 0 None None None 2026-08-31 12:14:37 UTC
Red Hat Product Errata RHBA-2026:62624 0 None None None 2026-09-02 12:18:03 UTC
Red Hat Product Errata RHBA-2026:66478 0 None None None 2026-09-10 17:42:55 UTC
Red Hat Product Errata RHSA-2026:60394 0 None None None 2026-08-27 08:55:40 UTC
Red Hat Product Errata RHSA-2026:61247 0 None None None 2026-08-31 04:42:36 UTC
Red Hat Product Errata RHSA-2026:61248 0 None None None 2026-08-31 03:37:44 UTC
Red Hat Product Errata RHSA-2026:89750 0 None None None 2026-10-26 03:04:49 UTC
Red Hat Product Errata RHSA-2026:89759 0 None None None 2026-10-26 03:20:15 UTC
Red Hat Product Errata RHSA-2026:90309 0 None None None 2026-10-26 15:41:33 UTC
Red Hat Product Errata RHSA-2026:92352 0 None None None 2026-10-29 13:33:01 UTC
Red Hat Product Errata RHSA-2026:92589 0 None None None 2026-10-29 19:49:36 UTC
Red Hat Product Errata RHSA-2026:93463 0 None None None 2026-11-02 03:33:01 UTC
Red Hat Product Errata RHSA-2026:93473 0 None None None 2026-11-02 03:23:01 UTC

Description OSIDB Bzimport 2026-06-29 14:01:41 UTC 
libxml2 is vulnerable to multiple stack-based buffer overflows in the xmlcatalog utility when running in --shell mode. The usershell() function processes user input using fixed-size stack buffers without proper bounds checking.
By supplying an overly long input line, an attacker can overflow internal buffers (command, arg, and argv) during input parsing. This results in memory corruption within the stack frame.
Successful exploitation may cause a crash or potentially allow arbitrary code execution in the context of the xmlcatalog process.

This issue has been fixed in the commit c2e233fc.

NOTE:
The maintainers of this project did not agree that this issue is a vulnerability and considered it a bug.
Comment 3 errata-xmlrpc 2026-08-27 08:55:37 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 10

Via RHSA-2026:60394 https://access.redhat.com/errata/RHSA-2026:60394
Comment 4 errata-xmlrpc 2026-08-31 03:37:42 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2026:61248 https://access.redhat.com/errata/RHSA-2026:61248
Comment 5 errata-xmlrpc 2026-08-31 04:42:33 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9

Via RHSA-2026:61247 https://access.redhat.com/errata/RHSA-2026:61247
Comment 6 Jon Orris 2026-10-26 03:04:47 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions

Via RHSA-2026:89750 https://access.redhat.com/errata/RHSA-2026:89750
Comment 7 Jon Orris 2026-10-26 03:20:13 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 10.0 Extended Update Support

Via RHSA-2026:89759 https://access.redhat.com/errata/RHSA-2026:89759
Comment 8 Jon Orris 2026-10-26 15:41:31 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.6 Extended Update Support

Via RHSA-2026:90309 https://access.redhat.com/errata/RHSA-2026:90309
Comment 9 Jon Orris 2026-10-29 13:32:59 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions

Via RHSA-2026:92352 https://access.redhat.com/errata/RHSA-2026:92352
Comment 10 Jon Orris 2026-10-29 19:49:33 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support
  Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On

Via RHSA-2026:92589 https://access.redhat.com/errata/RHSA-2026:92589
Comment 11 Jon Orris 2026-11-02 03:22:59 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support
  Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On

Via RHSA-2026:93473 https://access.redhat.com/errata/RHSA-2026:93473
Comment 12 Jon Orris 2026-11-02 03:32:59 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions
  Red Hat Enterprise Linux 8.8 Telecommunications Update Service

Via RHSA-2026:93463 https://access.redhat.com/errata/RHSA-2026:93463
Note You need to log in before you can comment on or make changes to this bug.