Potential security vulnerabilities have been identified in HP Easy Start for macOS

CVE-2026-12555 is a CWE-379 (insecure temporary file creation) vulnerability in the HP Easy Start Uninstaller component for macOS, affecting all versions prior to 2.16.7.260722. The uninstaller runs with root privileges after the user clicks through the macOS authorization prompt, and during execution it writes log and lock files to predictable, world-writable paths under /tmp and /private/tmp. A local attacker who pre-plants symlinks at those expected paths can redirect the root-privileged write to an arbitrary file — appending log content, not attacker-controlled payloads. The result is file corruption or creation of root-owned files, not direct code execution. Researcher Nir Yehoshua of Cipher Security Labs discovered this alongside two sibling CVEs (CVE-2026-12554, CVE-2026-12556), all patched in HP bulletin HPSBPI04124.

A CVSS 4.0 vector circulating on aggregator sites scores this at 7.7 (High) with AV:N — but that network-attack-vector designation is flatly wrong for a local symlink race condition. The actual attack requires local shell access on the target Mac *and* the victim to actively invoke the uninstaller with admin credentials. The payload is append-only log data, not arbitrary content. For an enterprise fleet, HP Easy Start is a consumer printer setup wizard — it is not a managed endpoint agent, not a server component, and not part of any enterprise deployment pipeline. The severity inflation here is a scoring artifact, not reality.

Why this verdict

• Local-only, victim-triggered attack: The attacker needs local shell access *and* must wait for a user to voluntarily uninstall HP Easy Start with admin credentials. There is no remote or automated trigger — this is a narrow, opportunistic, post-compromise escalation path.
• Uncontrolled payload content: Unlike a classic arbitrary-write primitive, the attacker can only redirect where log data is written, not *what* is written. This limits practical impact to file corruption or DoS. Achieving code execution requires chaining with a separate parsing vulnerability — none has been demonstrated.
• Role multiplier: HP Easy Start is a consumer printer setup utility for macOS. It is NOT a high-value-role component. It does not run on domain controllers, hypervisors, identity providers, CI/CD systems, backup servers, or network edge appliances. Its blast radius is a single macOS workstation (low-value role). The high-value-role floor does not apply — this component has essentially 0% presence in the high-value-role catalog.
• Aggregator CVSS vector is miscoded: The circulating CVSS 4.0 vector uses AV:N (Network) for what is demonstrably a local symlink race requiring physical or shell access. A corrected vector with AV:L/UI:R would score substantially lower, consistent with our LOW assessment.
• EPSS confirms low risk signal: At 0.23%, this CVE sits in the bottom quartile of exploitation probability, consistent with the narrow attack prerequisites and absent PoC.

Why not higher?

To reach MEDIUM or above, we would need either a remote attack vector, a broader installed base in enterprise environments, or evidence that the file-append primitive can be weaponized into code execution. None of these conditions exist. The component is consumer software with no network exposure, no PoC, and the payload is uncontrolled log data — the theoretical ceiling for this bug is workstation-scoped DoS.

Why not lower?

We stop at LOW rather than IGNORE because the vulnerability is real and confirmed: a local attacker *can* redirect root-privileged writes to arbitrary paths, and there are edge-case scenarios (corrupting a LaunchDaemon plist on a non-SIP-protected volume) where this could cause operational disruption on an individual Mac. The fix is available and trivial to apply, so documenting and patching during normal cycles is appropriate hygiene.

1. Uninstall HP Easy Start entirely from managed Macs — If your fleet doesn't need HP Easy Start (most enterprises use AirPrint, CUPS, or HP Easy Admin for managed deployments), remove it. This eliminates the attack surface completely. As a LOW-severity item, treat this as backlog hygiene — no mitigation SLA applies.
2. Deploy macOS configuration profile restricting /tmp symlink creation — Use an MDM profile or endpoint security policy to monitor or restrict symlink creation in /tmp and /private/tmp targeting sensitive system paths. This is a defense-in-depth measure, not specific to this CVE.
3. Ensure SIP (System Integrity Protection) is enabled — macOS SIP prevents even root from modifying protected system files (/System, /usr, etc.), which limits the blast radius of the symlink redirect. Verify SIP status across your fleet — csrutil status should report 'enabled' on all managed Macs.

Run this script on any macOS host where you want to check the HP Easy Start version. No special privileges required — it reads the application bundle's Info.plist. Example: bash check_cve_2026_12555.sh

#!/bin/bash
# check_cve_2026_12555.sh
# Checks whether HP Easy Start for macOS is installed and vulnerable to CVE-2026-12555
# Target: macOS hosts | Privileges: none (read-only plist check)
# Output: VULNERABLE / PATCHED / UNKNOWN

APP_PATH="/Applications/HP Easy Start.app"
PLIST="$APP_PATH/Contents/Info.plist"
FIXED_VERSION="2.16.7.260722"

if [ ! -d "$APP_PATH" ]; then
    echo "NOT APPLICABLE — HP Easy Start is not installed."
    exit 0
fi

if [ ! -f "$PLIST" ]; then
    echo "UNKNOWN — HP Easy Start found but Info.plist missing."
    exit 2
fi

INSTALLED_VERSION=$(/usr/libexec/PlistBuddy -c 'Print :CFBundleShortVersionString' "$PLIST" 2>/dev/null)

if [ -z "$INSTALLED_VERSION" ]; then
    echo "UNKNOWN — could not read version from Info.plist."
    exit 2
fi

echo "Installed HP Easy Start version: $INSTALLED_VERSION"
echo "Fixed version: $FIXED_VERSION"

# Compare versions using sort -V
LOWEST=$(printf '%s\n%s' "$FIXED_VERSION" "$INSTALLED_VERSION" | sort -V | head -n1)

if [ "$INSTALLED_VERSION" = "$FIXED_VERSION" ] || [ "$LOWEST" = "$FIXED_VERSION" ]; then
    echo "PATCHED — version $INSTALLED_VERSION >= $FIXED_VERSION."
    exit 0
else
    echo "VULNERABLE — version $INSTALLED_VERSION is below $FIXED_VERSION. CVE-2026-12555 applies."
    exit 1
fi

Sources

1. GBHackers — Three HP Easy Start Flaws Let Attackers Gain Root Privileges on macOS
2. Feedly CVE Intelligence — CVE-2026-12555
3. CyberPress — Three HP Easy Start Vulnerabilities Expose macOS Systems
4. OpenCVE — CVE-2026-12555
5. MITRE CWE-379 — Creation of Temporary File in Directory with Insecure Permissions
6. GitHub Advisory — GHSA-9jpq-gp3p-pv2f
7. CVE Details — CVE-2026-12555