unzip Unicode String null pointer dereference

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.0$0-$5k0.00

Summaryinfo

A vulnerability was found in unzip and classified as problematic. Affected by this issue is some unknown functionality of the component Unicode String Handler. The manipulation results in null pointer dereference. This vulnerability is known as CVE-2021-4217. It is possible to launch the attack remotely. No exploit is available.

Detailsinfo

A vulnerability, which was classified as problematic, was found in unzip (the affected version is unknown). Affected is an unknown code of the component Unicode String Handler. The manipulation with an unknown input leads to a null pointer dereference vulnerability. CWE is classifying the issue as CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. This is going to have an impact on availability. CVE summarizes:

A flaw was found in unzip. The vulnerability occurs due to improper handling of Unicode strings, which can lead to a null pointer dereference. This flaw allows an attacker to input a specially crafted zip file, leading to a crash or code execution.

The weakness was published 08/25/2022. The advisory is shared for download at access.redhat.com. This vulnerability is traded as CVE-2021-4217 since 01/27/2022. Successful exploitation requires user interaction by the victim. There are neither technical details nor an exploit publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 234300 (CBL Mariner 2.0 Security Update: unzip (CVE-2021-4217)), which helps to determine the existence of the flaw in a target environment.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at Tenable (234300). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Name

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

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

VulDB Base Score: 4.3
VulDB Temp Score: 4.3
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.8
NVD Vector: 🔍

CVSSv2info

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

Exploitinginfo

Class: Null pointer dereference
CWE: CWE-476 / CWE-404
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 234300
Nessus Name: CBL Mariner 2.0 Security Update: unzip (CVE-2021-4217)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔍

Timelineinfo

01/27/2022 🔍
08/25/2022 +209 days 🔍
08/25/2022 +0 days 🔍
04/14/2025 +963 days 🔍

Sourcesinfo

Advisory: access.redhat.com
Status: Not defined

CVE: CVE-2021-4217 (🔍)
GCVE (CVE): GCVE-0-2021-4217
GCVE (VulDB): GCVE-100-207120

Entryinfo

Created: 08/25/2022 08:57
Updated: 04/14/2025 20:39
Changes: 08/25/2022 08:57 (36), 09/25/2022 14:39 (11), 04/14/2025 20:39 (16)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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