fontconfig before 2.17.1 has an off-by-one error in allocation during sfnt capability handling, leading to a one-byte out-of-bounds write, and potentially a crash or code execution. This is in FcFontCapabilities in fcfreetype.c.

Mariner

Read the vendor bulletin Get alerts for azl3 fontconfig 2.14.2-1 on Azure Linux

5.9CVSS out of 10Medium severity

Scope

What the vendor says is affected

azl3 fontconfig 2.14.2-1 on Azure Linux 3.0

Timeline

When this advisory changed

Mar 27, 2026 at 1:01 AM UTC
Published by Microsoft Security Response Center
The publication date reported by the vendor.
Apr 22, 2026 at 1:41 AM UTC
Updated by Microsoft Security Response Center
The vendor changed the advisory after it was first published.
Oct 2, 2026 at 12:40 PM UTC
Added to SecurityAlert
We collected the advisory from the official source.
Oct 3, 2026 at 1:00 PM UTC
Confirmed at the source
Our collector saw this advisory during a later source check.

Vulnerabilities

CVEs named in this advisory

CVE-2026-34085View CVSS, KEV, EPSS, and threat context

Source

Start with the vendor's bulletin

SecurityAlert organizes the fields the vendor published. The original bulletin remains the source of record for affected versions, fixes, and later changes.

Vendor: Microsoft Security Response Center
Advisory ID: CVE-2026-34085
Last source check: Oct 3, 2026 at 1:00 PM UTC

Open the official bulletin How SecurityAlert builds this record

Your environment

Check the systems you actually run

A vendor advisory can tell you what may be affected. It cannot tell you whether that product and version are installed in your environment.

Confirm the product and installed version.
Read the vendor's prerequisites and exceptions.
Test the update or mitigation through your normal change process.

Watch azl3 fontconfig 2.14.2-1 on Azure Linux

Keep following

Get new Microsoft Security Response Center advisories

Use the vendor-specific RSS feed or set up alerts for a product your team relies on.

Follow this vendor's RSS feed

What the vendor says is affected

When this advisory changed

CVEs named in this advisory

Related advisories from Microsoft Security Response Center

netfilter: nf_tables: fix use-after-free in nf_tables_addchain()

SourcelessFileLoader does not use io.open_code()

Chromium: CVE-2025-10502 Heap buffer overflow in ANGLE

Libsoup: out-of-bounds read in libsoup handle_partial_get() leading to heap information disclosure

net: gso: Forbid IPv6 TSO with extensions on devices with only IPV6_CSUM

btrfs: qgroup: fix race between quota disable and quota rescan ioctl