zsh up to 5.8.0 PROMPT_SUBST Expansion privilege escalation

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
6.0$0-$5k0.00

Summaryinfo

A vulnerability was found in zsh up to 5.8.0. It has been classified as critical. This impacts an unknown function of the component PROMPT_SUBST Expansion Handler. The manipulation leads to an unknown weakness. This vulnerability is uniquely identified as CVE-2021-45444. The attack is possible to be carried out remotely. No exploit exists. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability was found in zsh up to 5.8.0 and classified as critical. This issue affects an unknown code block of the component PROMPT_SUBST Expansion Handler. Impacted is confidentiality, integrity, and availability.

The weakness was disclosed 02/14/2022. The advisory is shared at vuln.ryotak.me. The identification of this vulnerability is CVE-2021-45444 since 12/21/2021. Neither technical details nor an exploit are publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 239959 (TencentOS Server 3: zsh (TSSA-2022:0225)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.8.1 eliminates this vulnerability. The upgrade is hosted for download at zsh.sourceforge.io.

The vulnerability is also documented in the vulnerability database at Tenable (239959). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 6.0

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Privilege escalation
CWE: Unknown
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 239959
Nessus Name: TencentOS Server 3: zsh (TSSA-2022:0225)

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: zsh 5.8.1

Timelineinfo

12/21/2021 🔍
02/14/2022 +55 days 🔍
02/14/2022 +0 days 🔍
06/17/2025 +1219 days 🔍

Sourcesinfo

Advisory: FEDORA-2022-adf0c6d196
Status: Confirmed

CVE: CVE-2021-45444 (🔍)
GCVE (CVE): GCVE-0-2021-45444
GCVE (VulDB): GCVE-100-193037

Entryinfo

Created: 02/14/2022 18:35
Updated: 06/17/2025 20:34
Changes: 02/14/2022 18:35 (37), 02/17/2022 15:06 (2), 06/17/2025 20:34 (17)
Complete: 🔍
Cache ID: 216::103

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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