HighPublic exploit

Local Privilege Escalation in Apple OS X rsh remote_cmds via Environment Variables

IdentifiersCVE-2015-5889CWE-269

CVE-2015-5889 is a local privilege escalation vulnerability in the rsh program within Apple OS X's remote_cmds component affecting OS X versions before 10.11. The issue allows a local user to obtain root privileges through crafted use of environment variables. Public exploit material referenced in the provided content describes the bug as involving issetugid(), rsh, and libmalloc, indicating the flaw can be triggered in the context of privileged execution of rsh with attacker-controlled environment state. The vulnerability was used by FinSpy macOS malware as one of several public privilege-escalation options to gain root during installation on older macOS systems.

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ANALYST BRIEF

Impact, mitigation & remediation

What it means. What to do now. Patch path, mitigations, and the assume-compromise checklist.

Impact

What an attacker gets, and what they’ve been doing with it.

Successful exploitation allows a local, unprivileged user to escalate privileges to root on vulnerable OS X systems. This enables full compromise of the host, including installation of persistent system-level malware, modification of protected files and directories, loading or attempting to load privileged components, disabling or bypassing user-space protections, and access to sensitive data and system functionality otherwise restricted to root.

Mitigation

If you can’t patch tonight, do this now.

Until patching is completed, reduce exposure by restricting local code execution for untrusted users, monitoring for unexpected invocation of rsh and abnormal environment-variable usage in privileged contexts, and removing or disabling unnecessary legacy remote_cmds functionality where operationally feasible. Additional hardening measures include application whitelisting, least-privilege enforcement, and detection of post-exploitation artifacts associated with known malware leveraging this CVE.

Remediation

Patch, then assume compromise.

Upgrade affected Apple OS X systems to OS X 10.11 or later, as the vulnerability affects versions before 10.11. Remove or replace vulnerable remote_cmds/rsh components by applying Apple's security updates. In enterprise environments, prioritize patching legacy 10.9.x and 10.10.x systems that may still expose this local escalation path.

PUBLIC EXPLOITS

Exploits

1 valid exploit after Mallory filtered fakes, detection scripts, and README-only repos (1 hidden).

VALID 1 / 2 TOTALView more in app

rsh_libmalloc.rbMaturityWeaponizedFrameworkmetasploitVerified exploit

This repository contains a single Metasploit module (modules/exploits/osx/local/rsh_libmalloc.rb) that exploits a local privilege escalation vulnerability (CVE-2015-5889) in Mac OS X 10.9.5 and 10.10.5. The exploit abuses the rsh utility and the way malloc log files are handled to write to /etc/crontab, which is then used to append a passwordless sudo rule to /etc/sudoers. This allows the attacker to gain root privileges even if the root account is disabled. The module supports both x64 and Python payloads, which are executed as root after successful exploitation. The exploit requires a writable directory (default: /.Trashes) and a session on a vulnerable system. The code includes cleanup routines to restore the original crontab file. The main attack vector is local privilege escalation, and the primary fingerprintable endpoints are the system files /etc/sudoers, /etc/crontab, and /usr/bin/rsh.

Disclosed Oct 1, 2015rubylocal

EXPOSURE SURFACE

Affected products & vendors

Products and vendors Mallory has correlated with this vulnerability. Open in Mallory to drill down to specific CPE configurations and version ranges.

VendorProductType

AppleMac Os Xoperating_system

Vendor-confirmed product mapping. Mallory continuously reconciles this list against your asset inventory.

ACTIVITY FEED

Recent activity

3 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.

3 SOURCESView more in app

objective seeNews

Sep 26, 2020

FinFisher Filleted 🐟

A local privilege escalation vulnerability in macOS (OS X) that allows a local attacker to gain root privileges by exploiting the interaction between issetugid(), rsh, and libmalloc. Used by FinSpy macOS malware to escalate privileges.

amnesty internationalNews

Sep 25, 2020

German-made FinSpy spyware found in Egypt, and Mac and Linux versions revealed - Amnesty International

A macOS privilege escalation vulnerability used by the FinSpy for Mac OS infection chain to obtain root access during installation.

What this page doesn’t show

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Exposure mapping

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Threat actor evidence

Every observed campaign linking this CVE to a named adversary.

Associated malware1

Malware families riding this exploit, with evidence and IOCs.

Detection signatures

YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.

Vendor-by-vendor mapping

Cross-references every affected SKU, including bundled OEM variants.

Social activity