CVE-2021-39273

Exp

In XeroSecurity Sn1per 9.0 (free version), insecure permissions (0777) are set upon application execution, allowing an unprivileged user to modify the application, modules, and configuration files. This leads to arbitrary code execution with root privileges.

Published: 2021-08-19 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-39273 is rated High Exploit Risk (80.5/100): CVSS High severity, with medium exploitation likelihood (EPSS 2.67%). 2 public exploit reference(s) are indexed (Exploit-DB). EPSS rose +1.01% over the last day, indicating growing attacker interest. Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2021-39273

EDB-ID Source Kind Published Link
— nvd_ref exploit_tag Exploit-DB ↗
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2021-39273

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 1.66% 2.67% +1.01%
2 2025-11-21 2.25% 1.66% -0.59%
3 2025-11-18 — 2.25% —

Full EPSS history (17 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-39273

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.8 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 2.8 5.9 [email protected]
9.0 2.0 HIGH
AV:N/AC:L/Au:S/C:C/I:C/A:C Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:S)
A single authentication is required.
Confidentiality impact (C:C)
Complete confidentiality impact.
Integrity impact (I:C)
Complete integrity impact.
Availability impact (A:C)
Complete availability impact.
 8.0 10.0 [email protected]

Weakness enumeration for CVE-2021-39273

Affected software / configurations for CVE-2021-39273

Vendor Product Version Raw CPE
xerosecurity sn1per 9.0 cpe:2.3:a:xerosecurity:sn1per:9.0:*:*:*:*:*:*:*

References for CVE-2021-39273

URL Tags
https://github.com/1N3/Sn1per/issues/358 Exploit Third Party Advisory
https://github.com/1N3/Sn1per/releases Release Notes Third Party Advisory
https://github.com/nikip72/CVE-2021-39273-CVE-2021-39274 Exploit Third Party Advisory
cvelogic Threat Intelligence