CVE-2021-39273Public exploit

Root code execution via recursive permission changes

Published Aug 19, 2021 · Updated Aug 4, 2024

Privilege escalation in XeroSecurity Sn1per 9.0 allows local users to execute arbitrary code as root through world-writable files. The sniper script's init function recursively applies mode 0777 to the installation directory, making scripts and sourced configuration writable. Exploitation requires local write access and a later Sn1per launch by root, which executes the modified content with root privileges.

CVSS severity8.8
High
EPSS probability2.67%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Privilege escalation in XeroSecurity Sn1per 9.0 allows local users to execute arbitrary code as root through world-writable files. The sniper script's init function recursively applies mode 0777 to the installation directory, making scripts and sourced configuration writable. Exploitation requires local write access and a later Sn1per launch by root, which executes the modified content with root privileges.

The record

CVE
CVE-2021-39273
Published
Aug 19, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-276, T1574
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 19, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

9.0NIST NVDAV:N/AC:L/Au:S/C:C/I:C/A:C
8.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-276Incorrect Default Permissions
T1574Hijack Execution Flow

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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