X.Org X11 (libXfont2): Mehrere Schwachstellen ermöglichen Privilegieneskalation und Denial of Service

Summary

Product

Vulnerabilities 2

• Critical 9.0
  CVE-2026-44950

  fs_read_glyphs() heap buffer overflow via cumulative glyph data overflow in libXfont2

  fs_read_glyphs() in the libXfont2 font-server client (src/fc/fserve.c) copies each glyph's bitmap into a single buffer. Existing checks validates only that the source slice (position, length) lies within the source bitmap buffer. It does not check whether the…

  SUSE Image SLES15-SP6-SAP-Hardened-BYOS Image SLES15-SP7-SAP-GCE Image SLES-SAP-GCE-3P Debian Ubuntu Azure Linux
  Sep 10, 2026
• Critical 9.0
  CVE-2026-59679

  fs_read_glyphs() heap OOB read/write via encoding array index mismatch in libXfont2

  fs_read_glyphs() in the libXfont2 font-server client (src/fc/fserve.c) indexes the per-character encoding[] array using num_chars from the FS_QueryXBitmaps16 reply, but that array was allocated with a size derived from num_extents in the separate FS_QueryXExt…

  SUSE Image SLES15-SP6-SAP-Azure-3P Image SLES15-SP6-SAPCAL-Azure Image SLES15-SP7-SAPCAL-Azure Debian Ubuntu Azure Linux
  Sep 10, 2026

Revision history

1. 2026-09-29 #11

   Neue Updates von Oracle Linux aufgenommen

2. 2026-09-09 #10

   Referenz(en) aufgenommen: EUVD-2026-75300, EUVD-2026-75306

3. 2026-09-01 #9

   Neue Updates von Red Hat aufgenommen

4. 2026-08-31 #8

   Neue Updates von Red Hat und Amazon aufgenommen

5. 2026-08-24 #7

   Neue Updates von Red Hat aufgenommen

6. 2026-08-19 #6

   Neue Updates von Oracle Linux aufgenommen

7. 2026-08-17 #5

   Neue Updates von Oracle Linux und Rocky Enterprise Software Foundation aufgenommen

8. 2026-08-16 #4

   Neue Updates von Red Hat und SUSE aufgenommen

9. 2026-08-09 #3

   Neue Updates von openSUSE aufgenommen

10. 2026-08-05 #2

    Neue Updates von SUSE aufgenommen

11. 2026-08-04 #1

    Initiale Fassung

References

• X.Org Security Advisory vom 2026-08-04
  https://seclists.org/oss-sec/2026/q3/436
• SUSE Security Update SUSE-SU-2026:3500-1 vom 2026-08-05
  https://lists.suse.com/pipermail/sle-security-updates/2026-August/028147.html
• SUSE Security Update SUSE-SU-2026:3499-1 vom 2026-08-05
  https://lists.suse.com/pipermail/sle-security-updates/2026-August/028148.html
• openSUSE Security Update OPENSUSE-SU-2026:11463-1 vom 2026-08-08
  https://lists.opensuse.org/archives/list/security-announce@lists.opensuse.org/thread/PTGMTNHE2PKU34GA4TVT54ZYUWSQDO6P/
• Red Hat Security Advisory RHSA-2026:55447 vom 2026-08-17
  https://access.redhat.com/errata/RHSA-2026:55447
• SUSE Security Update SUSE-SU-2026:23151-1 vom 2026-08-14
  https://lists.suse.com/pipermail/sle-security-updates/2026-August/028300.html
• SUSE Security Update SUSE-SU-2026:23128-1 vom 2026-08-14
  https://lists.suse.com/pipermail/sle-security-updates/2026-August/028318.html
• Red Hat Security Advisory RHSA-2026:55448 vom 2026-08-17
  https://access.redhat.com/errata/RHSA-2026:55448
• Red Hat Security Advisory RHSA-2026:55446 vom 2026-08-17
  https://access.redhat.com/errata/RHSA-2026:55446
• Oracle Linux Security Advisory ELSA-2026-55447 vom 2026-08-17
  https://linux.oracle.com/errata/ELSA-2026-55447.html
• Oracle Linux Security Advisory ELSA-2026-55448 vom 2026-08-17
  https://linux.oracle.com/errata/ELSA-2026-55448.html
• Rocky Linux Security Advisory RLSA-2026:55446 vom 2026-08-17
  https://errata.build.resf.org/RLSA-2026:55446
• Rocky Linux Security Advisory RLSA-2026:55447 vom 2026-08-17
  https://errata.build.resf.org/RLSA-2026:55447
• Rocky Linux Security Advisory RLSA-2026:55448 vom 2026-08-17
  https://errata.build.resf.org/RLSA-2026:55448
• Oracle Linux Security Advisory ELSA-2026-55446 vom 2026-08-19
  https://linux.oracle.com/errata/ELSA-2026-55446.html
• Red Hat Security Advisory RHSA-2026:59312 vom 2026-08-25
  https://access.redhat.com/errata/RHSA-2026:59312
• Red Hat Security Advisory RHSA-2026:59311 vom 2026-08-25
  https://access.redhat.com/errata/RHSA-2026:59311
• Red Hat Security Advisory RHSA-2026:61390 vom 2026-09-01
  https://access.redhat.com/errata/RHSA-2026:61390
• Red Hat Security Advisory RHSA-2026:61755 vom 2026-08-31
  https://access.redhat.com/errata/RHSA-2026:61755
• Red Hat Security Advisory RHSA-2026:61756 vom 2026-08-31
  https://access.redhat.com/errata/RHSA-2026:61756
• Amazon Linux Security Advisory ALAS2-2026-3889 vom 2026-09-01
  https://alas.aws.amazon.com/AL2/ALAS2-2026-3889.html
• Amazon Linux Security Advisory ALAS2-2026-3890 vom 2026-09-01
  https://alas.aws.amazon.com/AL2/ALAS2-2026-3890.html
• Red Hat Security Advisory RHSA-2026:61995 vom 2026-09-01
  https://access.redhat.com/errata/RHSA-2026:61995
• Red Hat Security Advisory RHSA-2026:62231 vom 2026-09-01
  https://access.redhat.com/errata/RHSA-2026:62231
• Oracle Linux Security Advisory ELSA-2026-62231 vom 2026-09-29
  https://linux.oracle.com/errata/ELSA-2026-62231-0.html