#VU68298 NULL pointer dereference in UnZip - CVE-2021-4217

Vulnerability identifier: #VU68298

Vulnerability risk: Medium

CVSSv4.0: 4 [CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-4217

CWE-ID: CWE-476

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
UnZip
Client/Desktop applications / Software for archiving

Vendor: Info-ZIP

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to a NULL pointer dereference error in unzip when handling Unicode strings. A remote attacker can trick the victim to open a specially crafted archive and perform a denial of service (DoS) attack.

Mitigation
Cybersecurity Help is currently unaware of any official solution to address this vulnerability.

Vulnerable software versions

UnZip: 5.2 - 6.10c22

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External links
https://bugs.launchpad.net/ubuntu/+source/unzip/+bug/1957077
https://bugzilla.redhat.com/show_bug.cgi?id=2044583
https://access.redhat.com/security/cve/CVE-2021-4217

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.