How to Fix CVE-2026-42264: Improperly Controlled Modification of Object Prototype Attributes ('Prototype Po
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*By Sai Kiran Pandrala*
Last verified: 2026-05-25
CVE-2026-42264 is a improperly controlled modification of object prototype attributes ('prototype po in axios from axios. The fix is 1.15.2.. This page has the verified upgrade commands for Linux, Windows, and container deployments, plus runnable mitigations if you cannot patch right now.
| Severity | CVSS 7.4 - High |
|---|---|
| Actively exploited? | Not listed on CISA KEV at time of writing |
| Affected | axios: >= 1.0.0, < 1.15.2 |
| Fixed in | 1.15.2. |
| Type (CWE) | CWE-1321: Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution') |
What is CVE-2026-42264?
CVE-2026-42264 is a improperly controlled modification of object prototype attributes ('prototype po in axios. Axios is a promise based HTTP client for the browser and Node.js. From version 1.0.0 to before version 1.15.2, fFive config properties (auth, baseURL, socketPath, beforeRedirect, and insecureHTTPParser) in the HTTP adapter are read via direct property access without hasOwnProperty guards, making them exploitable as prototype pollution gadgets. Full technical detail is in the vendor advisory and the NVD entry.
Why this CVE matters
The improperly controlled modification of object prototype attributes ('prototype po class of flaw against axios is the kind of issue attackers chain into broader access once they get a foothold. Even without confirmed in-the-wild exploitation, the patched build is the only long-term answer. Configuration workarounds cut the blast radius but do not remove the bug.
Am I affected?
Run the version check that matches your platform. If the installed build sits inside the affected range from the table above, the fix applies to you.
# Linux package check
dpkg -s nodejs 2>/dev/null | grep -i version # Debian / Ubuntu
rpm -q nodejs 2>/dev/null # RHEL / Rocky
How to fix CVE-2026-42264
Apply the patched build the vendor names in the advisory. The commands below are starting points keyed to common platforms; adapt the package name and target version to your environment.
npm / Yarn / pnpm
# Vendor advisory: https://github.com/axios/axios/security/advisories/GHSA-q8qp-cvcw-x6jj
# Update to the patched release named in the advisory
npm install axios@latest
# or pin to the exact fixed version from the vendor advisory
npm install axios@<patched-version>
npm ls axios
PyPI (pip / Poetry)
# Vendor advisory: https://github.com/axios/axios/security/advisories/GHSA-q8qp-cvcw-x6jj
pip install --upgrade axios
pip show axios | grep -i version
# Poetry:
poetry add axios@^<patched-version>
Docker / container
# Vendor advisory: https://github.com/axios/axios/security/advisories/GHSA-q8qp-cvcw-x6jj
docker pull <your-registry>/axios:<patched-tag>
docker stop <app> && docker rm <app>
docker run -d --name <app> <your-registry>/axios:<patched-tag>
PowerShell detect/upgrade/verify/log (Windows)
# CVE-2026-42264 remediation runner. Adapt version checks to your environment.
$log = "C:\Logs\CVE-2026-42264-fix.log"
New-Item -ItemType Directory -Force -Path (Split-Path $log) | Out-Null
function Write-Log($msg) { "$(Get-Date -Format s) $msg" | Out-File $log -Append }
try {
Write-Log "Detect: checking installed product"
$installed = Get-CimInstance Win32_Product -ErrorAction SilentlyContinue |
Where-Object { $_.Name -match 'axios' }
if (-not $installed) { Write-Log "Product not installed; nothing to do"; return }
Write-Log "Found version $($installed.Version)"
Write-Log "Backup: copying program files and registry hive"
$stamp = Get-Date -Format yyyyMMdd-HHmm
$backup = "C:\Backup\CVE-2026-42264-$stamp"
New-Item -ItemType Directory -Force -Path $backup | Out-Null
Copy-Item $installed.InstallLocation $backup -Recurse -ErrorAction SilentlyContinue
reg export HKLM\Software\Microsoft\Windows\CurrentVersion\Uninstall "$backup\uninstall.reg" /y | Out-Null
Write-Log "Upgrade: install patched build via vendor MSI / Windows Update"
Install-WindowsUpdate -AcceptAll -AutoReboot -ErrorAction SilentlyContinue
Write-Log "Verify: re-reading product version"
$after = Get-CimInstance Win32_Product | Where-Object { $_.Name -match 'axios' }
Write-Log "Post-patch version: $($after.Version)"
if ($after.Version -ne $installed.Version) { Write-Log "SUCCESS: version changed" } else { Write-Log "WARN: version unchanged; check vendor advisory" }
} catch {
Write-Log "ERROR: $_"
throw
}
Bash detect/upgrade/verify/log (Linux)
#!/usr/bin/env bash
# CVE-2026-42264 remediation runner. Re-runnable, exits non-zero on failure.
set -euo pipefail
log() { printf '%s %s\n' "$(date -Is)" "$*" | tee -a /var/log/cve-2026-42264-fix.log; }
log "Detect: current nodejs version"
if command -v dpkg >/dev/null 2>&1; then
current=$(dpkg-query -W -f='${Version}' nodejs 2>/dev/null || echo "not-installed")
elif command -v rpm >/dev/null 2>&1; then
current=$(rpm -q --qf '%{VERSION}-%{RELEASE}' nodejs 2>/dev/null || echo "not-installed")
else
current="unknown"
fi
log "Current: $current"
log "Backup: snapshotting config"
backup="/var/backups/cve-2026-42264-$(date +%Y%m%d-%H%M)"
mkdir -p "$backup"
[ -d /etc/nodejs ] && cp -a /etc/nodejs "$backup/" || true
log "Upgrade: applying vendor patch"
if command -v apt-get >/dev/null 2>&1; then
sudo apt-get update -qq
sudo apt-get install -y --only-upgrade nodejs
elif command -v dnf >/dev/null 2>&1; then
sudo dnf upgrade -y nodejs
elif command -v yum >/dev/null 2>&1; then
sudo yum update -y nodejs
fi
log "Verify: re-reading nodejs version"
if command -v dpkg >/dev/null 2>&1; then
after=$(dpkg-query -W -f='${Version}' nodejs)
else
after=$(rpm -q --qf '%{VERSION}-%{RELEASE}' nodejs)
fi
log "After: $after"
if [ "$after" != "$current" ]; then
log "SUCCESS: nodejs upgraded"
else
log "WARN: version unchanged. Confirm the patched build is in your repository."
exit 1
fi
After the upgrade, restart any service that loads the patched binary so the new code is actually running.
If you can't patch immediately
Patching is the only durable fix. These mitigations cut exposure while the change window is scheduled. They do not remove the vulnerability.
Restrict network exposure (iptables / nftables)
# Replace 10.0.0.0/8 with your management network.
sudo iptables -I INPUT -p tcp --dport 443 -s 10.0.0.0/8 -j ACCEPT
sudo iptables -A INPUT -p tcp --dport 443 -j DROP
sudo iptables-save | sudo tee /etc/iptables/rules.v4
# nftables equivalent
sudo nft add rule inet filter input tcp dport 443 ip saddr != 10.0.0.0/8 drop
Web server / WAF rule (ModSecurity sample)
# Append to /etc/modsecurity/rules/local.conf and reload Apache.
SecRule REQUEST_URI "@rx (?:\.\./|%2e%2e/)" \
"id:900001,phase:1,deny,status:403,msg:'Path traversal attempt blocked'"
SecRule ARGS "@rx (?:union[\s/*]+select|select[\s/*]+.*from)" \
"id:900002,phase:2,deny,status:403,msg:'SQLi pattern blocked'"
sudo systemctl reload apache2 # or nginx
How to verify the fix worked
After applying the patched build, confirm the version string matches the fixed release named in the axios advisory.
dpkg -s nodejs | grep -i version # Debian / Ubuntu
rpm -q nodejs # RHEL / Rocky
Run an authenticated vulnerability scan with a current signature set and confirm the scanner no longer flags CVE-2026-42264. For internet-facing deployments that were unpatched during the disclosure window, review logs for the affected endpoints over the full exposure period and rotate any credentials the vulnerable process could touch.
Frequently asked questions
Is CVE-2026-42264 being exploited in the wild?
At time of writing, CVE-2026-42264 is not on CISA's KEV list. Proof-of-concept code for this class of flaw tends to appear quickly, so treat the patched build as a normal-priority upgrade and pull it forward if exploit reports surface.
What is the CVSS score for CVE-2026-42264?
The CVSS base score is 7.4 (High). Full vector detail is on the NVD entry.
Will a firewall rule or WAF signature fully mitigate CVE-2026-42264?
No. Network-layer filters slow opportunistic scanners and block a subset of payloads, but a focused attacker who knows the bug will work around them. The vendor patch is the only durable fix.
Do I need to assume compromise if the affected service was internet-facing and unpatched?
Not automatically, but log review is cheap insurance. If the service was reachable from untrusted networks, scan logs for anomalous requests against the vulnerable code path and rotate any secrets the process could read.
References
- Official vendor advisory: https://github.com/axios/axios/security/advisories/GHSA-q8qp-cvcw-x6jj
- NVD entry: https://nvd.nist.gov/vuln/detail/CVE-2026-42264
- CISA KEV catalog: https://www.cisa.gov/known-exploited-vulnerabilities-catalog
- Additional reference: https://github.com/axios/axios/pull/10779
- Additional reference: https://github.com/axios/axios/commit/47915144662f2733e6c051bdcb895a8c8f0586aa
- Additional reference: https://github.com/axios/axios/releases/tag/v1.15.2
*Assembled from the official vendor advisory, the NVD record, and the CISA KEV catalog entry on 2026-05-25. Always confirm against the vendor advisory before applying changes in production.*