CVE-2023-45666Public exploitNetwork attack vector

Code execution via stale GIF delays pointer

Published Oct 20, 2023 · Updated Feb 13, 2025

Double-free in Sean Barrett stb_image 2.28 and earlier allows attackers to execute code via crafted GIF data under allocation failure. The stbi__load_gif_main failure paths free the delays allocation without clearing the caller-visible pointer, while a later format-conversion failure can return NULL without freeing that allocation. Reachability requires an embedding application to request GIF frame delays, process attacker-controlled GIF data, encounter an allocation or conversion failure, and then free the stale pointer.

CVSS severity9.8
Critical
EPSS probability0.96%
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

Double-free in Sean Barrett stb_image 2.28 and earlier allows attackers to execute code via crafted GIF data under allocation failure. The stbi__load_gif_main failure paths free the delays allocation without clearing the caller-visible pointer, while a later format-conversion failure can return NULL without freeing that allocation. Reachability requires an embedding application to request GIF frame delays, process attacker-controlled GIF data, encounter an allocation or conversion failure, and then free the stale pointer.

The record

CVE
CVE-2023-45666
Published
Oct 20, 2023
Updated
Feb 13, 2025
Vendor
Sean Barrett
Product
stb
Classifications
CWE-415
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Oct 20, 2023CVE publishedPublication date reported by the CVE source.
  2. Feb 13, 2025Record 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=<= 2.28

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Sean Barrett · stbversion=<= 2.28
Sean Barrett · stb_imageversion=0 <=2.28

Published CVSS scores

7.3GitHub, Inc.CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
9.8NISTCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

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)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-415Double Free

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