zsh up to 5.4.2 Hash Table params.c input validation

CVSS Meta Temp Score
CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.
Current Exploit Price (≈)
Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.
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.
6.3$0-$5k0.00

Summaryinfo

A vulnerability was found in zsh up to 5.4.2. It has been classified as problematic. The impacted element is an unknown function of the file params.c of the component Hash Table Handler. This manipulation causes input validation. This vulnerability appears as CVE-2018-7549. The attack may be initiated remotely. There is no available exploit. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability classified as problematic was found in zsh up to 5.4.2. Affected by this vulnerability is an unknown code block of the file params.c of the component Hash Table Handler. The manipulation with an unknown input leads to a input validation vulnerability. The CWE definition for the vulnerability is CWE-20. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. As an impact it is known to affect availability. The summary by CVE is:

In params.c in zsh through 5.4.2, there is a crash during a copy of an empty hash table, as demonstrated by typeset -p.

The bug was discovered 02/27/2018. The weakness was presented 02/27/2018 with Red Hat (Website). It is possible to read the advisory at sourceforge.net. This vulnerability is known as CVE-2018-7549 since 02/27/2018. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Technical details of the vulnerability are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 109139 (Amazon Linux 2 : zsh (ALAS-2018-986)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Amazon Linux Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 157839 (Oracle Enterprise Linux Security Update for zsh (ELSA-2018-3073)).

Upgrading eliminates this vulnerability. A possible mitigation has been published 2 months after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Tenable (109139) and SecurityFocus (BID 103359†). See VDB-113890, VDB-113891, VDB-113902 and VDB-113903 for similar entries. Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.4
VulDB Meta Temp Score: 6.3

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.5
NVD Vector: 🔍

CVSSv2info

AVACAuCIA
💳💳💳💳💳💳
💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
UnlockUnlockUnlockUnlockUnlockUnlock
UnlockUnlockUnlockUnlockUnlockUnlock
UnlockUnlockUnlockUnlockUnlockUnlock

VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Input validation
CWE: CWE-20
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

0-DayUnlockUnlockUnlockUnlock
TodayUnlockUnlockUnlockUnlock

Nessus ID: 109139
Nessus Name: Amazon Linux 2 : zsh (ALAS-2018-986)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 65476
OpenVAS Name: Fedora Update for zsh FEDORA-2018-9cdf18a850
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
Exposure Time: 🔍

Patch: sourceforge.net

Timelineinfo

02/27/2018 🔍
02/27/2018 +0 days 🔍
02/27/2018 +0 days 🔍
02/27/2018 +0 days 🔍
02/28/2018 +1 days 🔍
03/09/2018 +9 days 🔍
04/05/2018 +27 days 🔍
04/18/2018 +13 days 🔍
02/16/2023 +1765 days 🔍

Sourcesinfo

Advisory: RHSA-2018:3073
Organization: Red Hat
Status: Confirmed

CVE: CVE-2018-7549 (🔍)
GCVE (CVE): GCVE-0-2018-7549
GCVE (VulDB): GCVE-100-113923
SecurityFocus: 103359 - Zsh 'exec.c:hashcmd()' Function Local Denial of Service Vulnerability

See also: 🔍

Entryinfo

Created: 02/28/2018 09:18
Updated: 02/16/2023 08:45
Changes: 02/28/2018 09:18 (73), 01/09/2020 11:24 (6), 02/16/2023 08:45 (5)
Complete: 🔍
Cache ID: 216::103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Discussion

No comments yet. Languages: en.

Please log in to comment.

◂ PreviousOverviewNext ▸

Want to know what is going to be exploited?

We predict KEV entries!