CVE-2026-18497Public exploit

Crash or heap disclosure via unchecked glyph pointer

Published Aug 7, 2026 · Updated Aug 7, 2026

Heap buffer overflow in Sean Barrett stb 1.26 and earlier allows attackers to crash applications or read adjacent heap data via malformed TTF files. stbtt__GetGlyphShapeTT() derives an iteration count from endPtsOfContours and executes flags = *points++ without checking the glyph-buffer boundary. A consuming application must load, bake, or render the crafted font; the demonstrated outcomes are information disclosure and a process crash.

CVSS severityUnavailable
Unscored
EPSS probability0.19%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Heap buffer overflow in Sean Barrett stb 1.26 and earlier allows attackers to crash applications or read adjacent heap data via malformed TTF files. stbtt__GetGlyphShapeTT() derives an iteration count from endPtsOfContours and executes flags = *points++ without checking the glyph-buffer boundary. A consuming application must load, bake, or render the crafted font; the demonstrated outcomes are information disclosure and a process crash.

The record

CVE
CVE-2026-18497
Published
Aug 7, 2026
Updated
Aug 7, 2026
Vendor
Sean Barrett
Product
stb
Classifications
CWE-122
Attack vector
Unavailable
Privileges
Unavailable

Timeline

How it unfolded

  1. Aug 7, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 7, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=1.26

What conditions does exploitation require?

Attack vectorUnavailable in this record.
Required privilegesUnavailable in this record.

What is affected?

Sean Barrett · stbversion=1.26

Published CVSS scores

No CVSS assessment is available in this record.

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
VectorUnavailable
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-122Heap-based Buffer Overflow

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo