CVE-2026-24811 – This CVE describes a vulnerability in the ROOT ... (How to Fix)

📋 TL;DR

This CVE describes a vulnerability in the ROOT data analysis framework's built-in zlib modules, specifically in the inffast.C program files. The vulnerability allows improper input validation (CWE-20) that could lead to memory corruption or crashes. This affects systems running ROOT software that utilize its zlib compression/decompression functionality.

💻 Affected Systems

Products:

ROOT data analysis framework

Versions: Specific versions not specified in provided information

Operating Systems: All platforms running ROOT

Default Config Vulnerable: ⚠️ Yes

Notes: Affects systems using ROOT's built-in zlib modules for compression/decompression operations

📦 What is this software?

Root by Root

View all CVEs affecting Root →

⚠️ Risk & Real-World Impact

🔴

Worst Case

Remote code execution leading to complete system compromise if the vulnerable component processes malicious input

🟠

Likely Case

Denial of service through application crashes or memory corruption when processing malformed compressed data

🟢

If Mitigated

Limited impact with proper input validation and sandboxing of ROOT processes

🌐 Internet-Facing: MEDIUM - ROOT is primarily used in scientific computing environments, not typically exposed directly to internet

🏢 Internal Only: MEDIUM - Internal systems using ROOT for data analysis could be affected by malicious data files

🎯 Exploit Status

Public PoC: ✅ No

Weaponized: UNKNOWN

Unauthenticated Exploit: ⚠️ Yes

Complexity: MEDIUM

Exploitation requires crafting malicious compressed data that triggers the vulnerability during processing

🛠️ Fix & Mitigation

✅ Official Fix

Patch Version: Version containing pull request #18526

Vendor Advisory: https://github.com/root-project/root/pull/18526

Restart Required: Yes

Instructions:

1. Update ROOT to version containing fix from pull request #18526
2. Recompile any applications using ROOT libraries
3. Restart services using ROOT functionality

🔧 Temporary Workarounds

Disable built-in zlib

all

Use system zlib library instead of ROOT's built-in implementation

Configure ROOT with --disable-builtin-zlib during compilation

Input validation

all

Implement strict validation of compressed data before processing

🧯 If You Can't Patch

Isolate ROOT processes in containers or sandboxes to limit potential damage
Implement network segmentation to restrict access to systems running ROOT

🔍 How to Verify

Check if Vulnerable:

Check ROOT version and verify if built with vulnerable inffast.C from zlib modules

Check Version:

root-config --version

Verify Fix Applied:

Verify ROOT version includes changes from pull request #18526

📡 Detection & Monitoring

Log Indicators:

ROOT process crashes
Memory access violation errors in ROOT logs
Unexpected termination of ROOT-based applications

Network Indicators:

Unusual data transfers to/from ROOT analysis systems

SIEM Query:

process_name:"root" AND (event_type:crash OR error_message:"segmentation fault" OR error_message:"memory corruption")

📊 Metadata

CVE ID: CVE-2026-24811

CVSS v3 Score: 9.8 (CRITICAL)

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

CWE: CWE-20

EPSS Score: 0.1% exploit probability (27.9th percentile)

Published: January 27, 2026

Last Updated: February 19, 2026

🔗 References

📤 Share & Export

📄 Export Markdown 📋 Export JSON

🔗 Related Vulnerabilities

If you're affected by CVE-2026-24811, you might also want to check these: