External risk intelligence

AnimatedGIF LZW Decode Buffer Overflow

CVE advisorySeverity: CRITICAL (CVSS 9.8)

CVE-2026-30141

A buffer overflow in the LZW Decode function of the AnimatedGIF software library can be exploited by a remote attacker providing a crafted GIF file. This vulnerability could lead to a denial of service, causing an application crash, or potentially allow for arbitrary code execution. The impact is significant if the aff

1Halo Surface Signal

Buffer Overflow

External exposure likelihood

Halo Surface Signal score for CVE-2026-30141

This vulnerability exists in a software library (AnimatedGIF) used for processing image files. It is not a standalone network service, edge gateway, or web application. Vulnerabilities in image parsing libraries are typically triggered by local file processing or within client-side applications rather than via direct, predictable exposure of an internet-facing network surface.

PCI scan relevance

PCI Relevance for CVE-2026-30141

Yes

CVE-2026-30141 — Halo PCI Relevance: Yes. Under typical PCI ASV external scan criteria, this issue may be flagged for scan prioritization.

This vulnerability allows remote attackers to cause a denial of service or execute arbitrary code, which can lead to an ASV scan failure for PCI compliance.

Scan-prioritization guidance only—not a PCI DSS certification or ASV attestation.

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Horizon Alert

Summary of the vulnerability and why it matters

A buffer overflow vulnerability has been identified in the AnimatedGIF software library that could allow a remote attacker to crash the application or potentially execute unauthorized code by sending a specially crafted GIF file.

  • Allows code execution or denial of service.
  • Matters if processing untrusted image files.
  • Confirm relevance and assess potential exposure.

Attack Path

How an attacker could exploit the issue

An attacker can send a specially crafted GIF file to a system processing these images. This malicious file targets a flaw in the LZW decoding process, potentially leading to a program crash or enabling the attacker to run their own code.

  • No entry conditions required.
  • Triggered by processing a malicious GIF.
  • Leads to code execution or crash.

Live Threat

Current exploitation, exposure, and threat context

A buffer overflow in the LZW decoding function of AnimatedGIF could allow an attacker to crash the service or potentially execute arbitrary code when processing a specially crafted GIF file. This could impact the availability of services that process GIFs.

  • System data integrity and availability.
  • Malicious GIF processed by the service.
  • Service disruption or code execution.

Priority actions

Operational Fix

Recommended remediation, mitigation, and detection steps

This critical vulnerability in the AnimatedGIF library's LZW decoding function requires immediate attention. Application owners integrating this library are primarily responsible for remediation, supported by platform or infrastructure teams for deployment. The first practical step involves identifying all instances where AnimatedGIF is used, confirming business criticality and network reachability, and then planning remediation based on the assessed risk.

  • Application owners must own the issue.
  • Verify reachability and business criticality first.
  • Plan remediation based on assessed risk.

Frequently asked questions

What is bitbank2 AnimatedGIF?

bitbank2 AnimatedGIF is a software library designed to help developers read, parse, and display animated GIF files within their own applications. Because it is a library rather than a standalone program, it functions as a modular component that developers embed into various software projects—such as image viewers, content management systems, or custom media processing tools—to handle graphical data efficiently.

How does CVE-2026-30141 create a buffer overflow?

This vulnerability is classified as CWE-120, a classic buffer overflow. It occurs during the LZW decoding phase, where the software attempts to write data from a GIF file into a memory buffer. If the file is specifically crafted to exceed the buffer's capacity, it overwrites adjacent memory. This corruption can crash the application or, in more severe cases, allow an attacker to hijack the program's execution flow.

Do I need to be tricked into opening a file to trigger this?

The vulnerability is triggered whenever the library processes a malicious GIF file. It does not require user interaction, such as clicking a link or manually opening an image. Any automated service, backend script, or application that attempts to decode an untrusted GIF file provided by an attacker can be forced to process the malicious data, triggering the flaw automatically.

Is my system at risk if it isn't internet-facing?

Halo Surface Signal notes that since this is a library for processing images, the risk depends on where your application encounters untrusted GIFs. While internet-facing services are more easily reached by attackers, any application that processes files from email attachments, user uploads, or internal data streams remains a potential target if it handles external or unverified image content.

What should I do if I use AnimatedGIF?

Start by performing a dependency audit to locate all applications in your environment that rely on the AnimatedGIF library. Once identified, evaluate whether those applications process images from untrusted or external sources. Prioritize updating the library to a patched version once available, and consider implementing stricter input validation to filter suspicious files before they reach the decoding logic.

References

Sources and related resources

Primary sources: NVD, CVE.org.

NVDPublished Modified