CVE-2026-34458

CVE-2026-34458 is a high-severity vulnerability in Sandboxie-plus Sandboxie with a CVSS 3.x base score of 8.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-93.

Key facts

Description

Sandboxie-Plus is an open source sandbox-based isolation software for Windows. In versions 1.17.2 and earlier, an INI injection vulnerability allows any standard local user to bypass configuration restrictions (EditAdminOnly and ConfigPassword) and inject arbitrary directives into the global Sandboxie.ini configuration file. The background service skips authorization checks for IPC messages targeting sections beginning with UserSettings_, but does not sanitize CRLF characters in either the value parameter (via MSGID_SBIE_INI_ADD_SETTING) or the setting name parameter (via MSGID_SBIE_INI_SET_SETTING). An attacker can inject a new sandbox section header with unrestricted permissions, enabling sandbox escape and SYSTEM privilege escalation. This issue has been fixed in version 1.17.3.

Frequently asked questions

What is CVE-2026-34458?
Sandboxie-Plus is an open source sandbox-based isolation software for Windows. In versions 1.17.2 and earlier, an INI injection vulnerability allows any standard local user to bypass configuration restrictions (EditAdminOnly and ConfigPassword) and inject arbitrary directives into the global Sandboxie.ini configuration file. The background service skips authorization checks for IPC messages targeting sections beginning with UserSettings_, but does not sanitize CRLF characters in either the value parameter (via MSGID_SBIE_INI_ADD_SETTING) or the setting name parameter (via MSGID_SBIE_INI_SET_SETTING). An attacker can inject a new sandbox section header with unrestricted permissions, enabling sandbox escape and SYSTEM privilege escalation. This issue has been fixed in version 1.17.3.
How severe is CVE-2026-34458?
CVE-2026-34458 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-34458 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (16th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-34458?
CVE-2026-34458 affects Sandboxie-plus Sandboxie. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-34458?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-34458 have an EU (EUVD) identifier?
Yes. CVE-2026-34458 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-27456.
When was CVE-2026-34458 published?
CVE-2026-34458 was published on 2026-05-05 and last updated on 2026-06-17.

References

Affected products (1)

More vulnerabilities in Sandboxie-plus Sandboxie

All CVEs affecting Sandboxie-plus Sandboxie →

Other CWE-93 (CRLF Injection) vulnerabilities

Browse all CWE-93 (CRLF Injection) vulnerabilities →