CVE-2026-34596
📛 CVE Title
Sandboxie-Plus local privilege escalation via TOCTOU race condition in UpdUtil addon installation
Description
Sandboxie-Plus is an open source sandbox-based isolation software for Windows. In versions 1.17.2 and earlier, a Time-of-Check-to-Time-of-Use (TOCTOU) race condition exists during addon installation. When a user installs an addon through the SandMan interface, UpdUtil.exe is spawned as SYSTEM by SbieSvc but stages files in the user-writable %TEMP%\sandboxie-updater directory. After UpdUtil verifies file hashes against the signed addon manifest, install.bat extracts files.cab and executes config.exe from its contents. Between hash verification and extraction, an unprivileged user can replace files.cab with a crafted cabinet containing a malicious executable, which is then run as SYSTEM. No UAC prompt is required. This issue has been fixed in version 1.17.3.
Overview
- State
- PUBLISHED
- Assigner (CNA)
- GitHub_M
- CVSS severity
- MEDIUM
- CVSS score
- 5.4 / 10
- CVSS vector
CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N- Effective score
- 5.4 / 10 MEDIUM source: CNA overview
- CWE(s)
-
CWE-367 - Reserved
- 2026-03-30
- Published
- 2026-05-05 19:34 UTC
- Last updated
- 2026-05-07 03:55 UTC
- Source
- https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/34xxx/CVE-2026-34596.json
- Linked Threat
- CVE-2026-34596 — CVE-2026-34596
NVD triage scoring NVD CVE 2.0
Layer NVD adds on top of the CNA's CVE record — published / last-modified timestamps, exploitability / impact subscores, and the FIRST.org EPSS probability that this CVE will be exploited in the wild in the next 30 days.
- NVD published
- 2026-05-05 20:16:38 UTC
- NVD last modified
- 2026-05-07 19:45:53 UTC
- NVD CVSS v3.1
- 7.0 / 10 HIGH source: nvd@nist.gov
- NVD CVSS vector
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H- Exploitability subscore
- 1.0 / 10
- Impact subscore
- 5.9 / 10
- EPSS score
- 0.0001 (probability of exploitation in next 30 days)
- EPSS percentile
- 2.27% vs all CVEs — higher = more likely to be exploited, as of 2026-05-24
NVD / KEV / EPSS data refreshed 2026-05-25 02:38 UTC. Re-run the 🛰 Backfill from NVD button above to refresh.
European Union Vulnerability Database ENISA EUVD
ENISA's official EU repository for curated vulnerability intelligence. Carries a separate identifier (EUVD-YYYY-NNNN) and frequently exposes an earlier-published description + CVSS than NVD does.
- EUVD ID
-
EUVD-2026-27468 - Assigner
- GitHub_M
- Published
- May 5, 2026, 7:34:50 PM
- Updated
- May 7, 2026, 3:55:42 AM
- EUVD base score (CVSS 4.0)
-
5.4 / 10
CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N - EUVD-reported EPSS
- 0.0100
- Vendors
- sandboxie-plus
- Products
-
Sandboxie (< 1.17.3)
ENISA description: Sandboxie-Plus is an open source sandbox-based isolation software for Windows. In versions 1.17.2 and earlier, a Time-of-Check-to-Time-of-Use (TOCTOU) race condition exists during addon installation. When a user installs an addon through the SandMan interface, UpdUtil.exe is spawned as SYSTEM by SbieSvc but stages files in the user-writable %TEMP%\sandboxie-updater directory. After UpdUtil verifies file hashes against the signed addon manifest, install.bat extracts files.cab and executes config.exe from its contents. Between hash verification and extraction, an unprivileged user can replace files.cab with a crafted cabinet containing a malicious executable, which is then run as SYSTEM. No UAC prompt is required. This issue has been fixed in version 1.17.3.
Affected products (1)
| Vendor | Product | Versions | Platforms |
|---|---|---|---|
| sandboxie-plus | Sandboxie |
< 1.17.3 (affected)
|
— |
Affected products — CPE 2.3 (1) NVD
NVD's normalized CPE 2.3 matchers, used by vendor tools (vulnerability scanners, asset managers) for automated detection. Compare with the CNA's free-text "Affected products" section above.
cpe:2.3:a:sandboxie-plus:sandboxie:*:*:*:*:plus:*:*:*
Vendor references (1)
References embedded in the original CVE record by the assigning CNA.
Web references (4)
DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.
- https://github.com/sandboxie-plus/Sandboxie/security/advisories/GHSA-xjvp-63f2-v585 tenable:github.com
- https://nvd.nist.gov/vuln/detail/CVE-2026-34596 tenable:nvd.nist.gov
- https://www.cve.org/CVERecord?id=CVE-2026-34596 tenable:www.cve.org
- https://www.first.org/epss/ tenable:www.first.org
NVD-tagged references (2)
Reference list NVD curates from the CNA record, vendor advisories, and third-party reports. The tag chips below are NVD's analyst-assigned categories.
- https://github.com/sandboxie-plus/Sandboxie/security/advisories/GHSA-xjvp-63f2-v585 security-advisories@github.com ExploitVendor Advisory
- https://github.com/sandboxie-plus/Sandboxie/security/advisories/GHSA-xjvp-63f2-v585 134c704f-9b21-4f2e-91b3-4a467353bcc0 ExploitVendor Advisory
Remediations (20)
Remediations are stored against the linked Threat row; the list below is deduplicated across both pages.
-
web:attack.mitre.org
This mitigation can be implemented through the following measures: Regular Operating System Updates Implementation: Apply the latest Windows security updates monthly using WSUS (Windows Server Update Services) or a similar patch management solution. Configure systems to check for updates automatically and schedule reboots during maintenance ...
2026-05-23 21:49 UTC -
web:blog.qualys.com
Microsoft has rolled out its March 2026 Patch Tuesday updates, delivering a fresh batch of security fixes designed to keep Windows environments protected from emerging threats.
2026-05-23 21:49 UTC -
web:blog.talosintelligence.com
Microsoft has released its monthly security update for May 2026 , which includes 137 vulnerabilities affecting a range of products, including 16 that Microsoft marked as "critical".
2026-05-23 21:49 UTC -
web:integsec.com
Meta Description: Critical remote code execution in Microsoft Windows DNS Client (CVE‑2026‑41096) exposes business systems in the United States and Canada; learn risk, impact, and response steps.
2026-05-23 21:49 UTC -
web:krebsonsecurity.com
For a clickable, per- patch breakdown, check out the SANS Internet Storm Center Patch Tuesday roundup. Running into problems applying any of these updates?
2026-05-23 21:49 UTC -
web:portal.msrc.microsoft.com
The Security Update Guide provides information on the latest Microsoft security updates, helping users understand and address potential vulnerabilities effectively.
2026-05-23 21:49 UTC -
web:securityboulevard.com
Cybersecurity vulnerabilities pose significant risks to organizations in today's digital landscape. Left unaddressed, these vulnerabilities can lead to data breaches, financial losses, and reputational damage. Organizations must decide how to tackle vulnerabilities—through remediation , mitigation , or a combination of both. But which strategy is more effective? This blog explores the ...
2026-05-23 21:49 UTC -
web:www.bugcrowd.com
Vulnerability mitigation is typically considered a temporary or interim solution. While mitigation measures can reduce the immediate risk associated with vulnerabilities, they may not provide a permanent fix . Organizations should aim to prioritize and plan for complete vulnerability remediation whenever feasible and allocate resources accordingly.
2026-05-23 21:49 UTC -
web:www.ontinue.com
Mitigation helps identify and manage vulnerabilities, and if the resources and skills are available, those weaknesses can move from mitigation to remediation . Mitigation is often the answer instead of remediation for issues like: A fix or patch of software isn't immediately available, so the update that would remediate the issue is postponed.
2026-05-23 21:49 UTC -
web:www.zafran.io
Mitigation is the control implemented or the action taken to reduce the impact or likelihood of a vulnerability or exposure being exploited before a fix is available or applied. Remediation is the resolution of the vulnerability or exposure which is completed typically through applying patches, updates, or correcting misconfigurations.
2026-05-23 21:49 UTC -
web:msrc.microsoft.com
Security Update Guide - Microsoft Security Response Center
2026-05-26 02:46 UTC -
web:thehackernews.com
Microsoft patched 138 flaws, including 30 Critical bugs, as AI discovery expands Patch Tuesday risk.
2026-05-26 02:46 UTC -
web:threatprotect.qualys.com
Zero-day Vulnerabilities Patched in April Patch Tuesday Edition CVE - 2026 -33825: Microsoft Defender Elevation of Privilege Vulnerability Microsoft Defender is a comprehensive, AI-powered security suite that provides malware protection, phishing detection, and web protection for individuals and businesses.
2026-05-26 02:46 UTC -
web:vulert.com
Microsoft's May 2026 Patch Tuesday fixes 138 vulnerabilities, including critical Windows DNS and Netlogon RCE flaws. Learn the risks, key CVEs , mitigation steps, and how Vulert can help.
2026-05-26 02:46 UTC -
web:windowsreport.com
Microsoft has released its May 2026 Patch Tuesday updates for Windows 11 and Windows 10, shipping as KB5089549 and KB5087544. The updates include fixes for more than 130 security vulnerabilities across Windows, Office, SharePoint, DNS components, and core system services, as Bleeping Computer writes. While no publicly disclosed zero-day vulnerabilities were reported this month, the […]
2026-05-26 02:46 UTC -
web:www.bleepingcomputer.com
Today is Microsoft's April 2026 Patch Tuesday with security updates for 167 flaws, including 2 zero-day vulnerabilities.
2026-05-26 02:46 UTC -
web:www.crowdstrike.com
Microsoft has released security updates for 130 vulnerabilities, including 30 critical, in its May 2026 Patch Tuesday rollout.
2026-05-26 02:46 UTC -
web:www.cve.org
At cve .org, we provide the authoritative reference method for publicly known information-security vulnerabilities and exposures
2026-05-26 02:46 UTC -
web:www.lansweeper.com
Which vulnerabilities, issues, and other things did Microsoft update? Discover what's new using Lansweeper's Patch Tuesday May 2026 summary.
2026-05-26 02:46 UTC -
web:zecurit.com
Get the complete breakdown of Microsoft's May 2026 Patch Tuesday. We analyze the latest security updates and all critical CVEs .
2026-05-26 02:46 UTC
AI Forensic Analysis
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Raw JSON
The full cvelistV5 record. Download as CVE-2026-34596.json.
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