How to Fix CVE-2026-40499: OS command injection in radare2
By Sai Kiran Pandrala. Last verified: 2026-05-25.
| Severity | 8.4 (High) |
|---|---|
| Actively exploited? | No public listing in CISA KEV |
| Affected | radareorg radare2 0 to <6.1.4 |
| Fixed in | radare2 6.1.4 |
| Type (CWE) | CWE-78: Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection') |
What is CVE-2026-40499?
radare2 prior to version 6.1.4 contains a command injection vulnerability in the PDB parser's print_gvars() function that allows attackers to execute arbitrary commands by embedding a newline byte in the PE section header name field. Attackers can craft a malicious PDB file with specially crafted section names to inject r2 commands that are executed when the idp command processes the file.
Am I affected?
Run the version check that matches your platform:
# Linux
dpkg -s radare2 2>/dev/null | grep -i version
rpm -q radare2 2>/dev/null
radare2 --version 2>/dev/null
Compare what you see against the Affected row above (radareorg radare2 0 to <6.1.4). If your build sits inside that range, you are exposed and should patch.
How to fix CVE-2026-40499
The primary fix is to upgrade radare2 to the patched build. Use the commands for your platform below; the patched version listed in the vendor advisory is: radare2 6.1.4.
Ubuntu / Debian
sudo apt-get update
sudo apt-get install --only-upgrade radare2
radare2 --version 2>/dev/null || dpkg -s radare2 | grep -i version
RHEL / CentOS / Rocky / AlmaLinux
sudo dnf upgrade --security radare2 -y
rpm -q radare2
SUSE / openSUSE
sudo zypper patch --category security
rpm -q radare2
Complete PowerShell remediation script (Windows)
# Fix script for CVE-2026-40499 affecting radare2
# Run as administrator. Detect -> backup -> upgrade -> verify -> log.
$ErrorActionPreference = "Stop"
$LogPath = "C:\Logs\CVE-2026-40499-fix-$(Get-Date -Format yyyyMMdd-HHmmss).log"
New-Item -ItemType Directory -Force (Split-Path $LogPath) | Out-Null
Start-Transcript -Path $LogPath -Append
try {
Write-Host "[1/4] Detecting installed version of radare2"
$pkg = winget list --id "radare2" 2>$null
Write-Host $pkg
Write-Host "[2/4] Backing up configuration"
$backup = "C:\Backup\radare2-$(Get-Date -Format yyyyMMdd)"
New-Item -ItemType Directory -Force $backup | Out-Null
Get-ChildItem "C:\ProgramData\radare2" -ErrorAction SilentlyContinue |
Copy-Item -Destination $backup -Recurse -Force -ErrorAction SilentlyContinue
Write-Host "[3/4] Applying upgrade to radare2 6.1.4"
winget upgrade --id "radare2" --silent --accept-source-agreements --accept-package-agreements
# Fallback: Windows Update for OS-level fixes
if ($LASTEXITCODE -ne 0) {
Install-Module -Name PSWindowsUpdate -Force -SkipPublisherCheck -ErrorAction SilentlyContinue
Import-Module PSWindowsUpdate
Install-WindowsUpdate -MicrosoftUpdate -AcceptAll -IgnoreReboot
}
Write-Host "[4/4] Verifying patched build"
winget list --id "radare2"
Write-Host "Fix applied. Reboot if prompted."
exit 0
} catch {
Write-Error "Patch failed: $_"
exit 1
} finally {
Stop-Transcript
}
Complete Bash remediation script (Linux)
#!/usr/bin/env bash
# Fix script for CVE-2026-40499 affecting radare2
# Detect -> backup -> upgrade -> verify -> log.
set -euo pipefail
LOG="/var/log/cve-2026-40499-fix-$(date +%Y%m%d-%H%M%S).log"
exec > >(tee -a "$LOG") 2>&1
echo "[1/4] Detecting installed version"
if command -v dpkg >/dev/null; then
dpkg -s radare2 2>/dev/null | grep -i version || echo "radare2 not installed via dpkg"
elif command -v rpm >/dev/null; then
rpm -q radare2 || echo "radare2 not installed via rpm"
fi
echo "[2/4] Backing up configuration"
BACKUP="/root/backup-cve-2026-40499-$(date +%Y%m%d)"
mkdir -p "$BACKUP"
for d in /etc/radare2 /etc/radare2.d /etc/radare2.conf; do
[ -e "$d" ] && cp -a "$d" "$BACKUP/" || true
done
echo "[3/4] Applying upgrade (target: radare2 6.1.4)"
if command -v apt-get >/dev/null; then
apt-get update
apt-get install --only-upgrade -y radare2
elif command -v dnf >/dev/null; then
dnf upgrade --security -y radare2
elif command -v yum >/dev/null; then
yum update -y radare2
elif command -v zypper >/dev/null; then
zypper --non-interactive patch --category security
fi
echo "[4/4] Verifying patched build"
if command -v dpkg >/dev/null; then
dpkg -s radare2 2>/dev/null | grep -i version
elif command -v rpm >/dev/null; then
rpm -q radare2
fi
echo "Done. Restart any running daemons that loaded the old library."
If you can't patch immediately
If you cannot apply the patched version today, restrict exposure with one of the following runnable controls. None replace the patch.
Network restriction (Linux, nftables)
# Block inbound traffic to the affected service from untrusted networks
sudo nft add table inet filter
sudo nft 'add chain inet filter input { type filter hook input priority 0 ; }'
sudo nft 'add rule inet filter input tcp dport {443, 80} ip saddr != 10.0.0.0/8 drop'
sudo nft list ruleset
Service-level fallback
# If the affected feature is optional, stop the service until the patch is applied
sudo systemctl stop radare2
sudo systemctl disable radare2
How to verify the fix worked
# Linux
radare2 --version 2>/dev/null || dpkg -s radare2 | grep -i version
rpm -q radare2 2>/dev/null || true
# Windows
winget list | findstr /I "radare2"
Get-HotFix | Sort-Object InstalledOn -Descending | Select-Object -First 5
Expected: the reported version is at or above radare2 6.1.4. Restart any services that loaded the old library (systemctl restart <service> on Linux, restart the Windows service or reboot when prompted). For network appliances, run show version on the device and confirm the build matches the patched release.
Frequently asked questions
Related fixes
Other vulnerabilities in the same area that are worth patching alongside this one:
- How to Fix CVE-2026-4660: Information disclosure in Tooling — Information disclosure in Tooling
- How to Fix CVE-2026-42050: Stack-based Buffer Overflow in ImageMagick — Stack-based Buffer Overflow in ImageMagick
- How to Fix CVE-2026-32500: Critical Vulnerability in MetaMax , Critical Vulnerability in MetaMax
- How to Fix CVE-2026-38991: n/a in n/a , n/a in n/a
- How to Fix CVE-2026-5837: PHPGurukul News Portal Project news-details.php sql injection , PHPGurukul News Portal Project news-details.php sql injection
Is CVE-2026-40499 actually being exploited?
According to the data sources above, no public confirmation of in-the-wild exploitation at this time. Either way, the fix is the same: apply the vendor patch.
Do I need to reboot after patching?
For OS or kernel updates, yes. For most userland packages a systemctl restart <service> is enough. Any process that loaded the old shared library keeps using it until restarted, so when in doubt, reboot.
What is the CVSS score?
8.4 (high). Refer to the vendor advisory for the exact vector string.
Where is the official advisory?
See the References section at the bottom of this page; the vendor's URL is the authoritative source for affected builds and patched versions.
References
- Official vendor advisory: https://github.com/radareorg/radare2/commit/5590c87deeb7eb2a106fd7aab9ca88bfeebb7397
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-40499
- https://github.com/radareorg/radare2/issues/25752
- https://github.com/radareorg/radare2/releases/tag/6.1.4
- https://www.vulncheck.com/advisories/radare2-command-injection-via-pdb-parser-print-gvars
*Written by Sai Kiran Pandrala. Assembled from the official vendor advisory, NVD record, and CISA KEV listing on 2026-05-25. Always confirm against the vendor's advisory before applying changes in production.*