#VU18058 NULL pointer dereference in Tar - CVE-2019-9923

Vulnerability identifier: #VU18058

Vulnerability risk: Low

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:Clear]

CVE-ID: CVE-2019-9923

CWE-ID: CWE-476

Exploitation vector: Network

Exploit availability: No

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

Vendor: GNU

Description

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

The vulnerability exists due to a NULL pointer dreference error in sparse.c in when parsing certain archives that have malformed extended headers. A remote attacker can perform a denial of service (DoS) attack.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Tar: 1.13 - 1.31

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External links
https://git.savannah.gnu.org/cgit/tar.git/commit/?id=cb07844454d8cc9fb21f53ace75975f91185a120
https://savannah.gnu.org/bugs/?55369
https://bugs.launchpad.net/ubuntu/+source/tar/+bug/1810241

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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.