Denial of service in libxls

1) NULL pointer dereference

EUVDB-ID: #VU50921

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-2020-27819

CWE-ID: CWE-476 - NULL Pointer Dereference

Exploit availability: No

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 within the libxls/xls2csv.c file in libxls when parsing XLS cells. A remote attacker can trigger denial of service conditions via crafted XLS file.

Mitigation

Install update from vendor's website.

Vulnerable software versions

libxls: 0.2.0 - 1.6.2 rc0

CPE2.3

• cpe:2.3:a:libxls_sourceforge_net:libxls:0.2.0:*:*:*:*:*:*:*
• cpe:2.3:a:libxls_sourceforge_net:libxls:0.3.0:*:*:*:*:*:*:*
• cpe:2.3:a:libxls_sourceforge_net:libxls:1.0.0:*:*:*:*:*:*:*

External links

https://bugzilla.redhat.com/show_bug.cgi?id=1903296
https://github.com/libxls/libxls/issues/84

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.