GNU tar up to 1.31 sparse.c pax_decode_header null pointer dereference

Summaryinfo

A vulnerability has been found in GNU tar up to 1.31 and classified as problematic. Affected by this vulnerability is the function pax_decode_header of the file sparse.c. This manipulation causes null pointer dereference. This vulnerability is handled as CVE-2019-9923. The attack can be initiated remotely. There is not any exploit available. The affected component should be upgraded.

Detailsinfo

A vulnerability classified as problematic was found in GNU tar up to 1.31. Affected by this vulnerability is the function pax_decode_header of the file sparse.c. The manipulation with an unknown input leads to a null pointer dereference vulnerability. The CWE definition for the vulnerability is 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. As an impact it is known to affect availability. The summary by CVE is:

pax_decode_header in sparse.c in GNU Tar before 1.32 had a NULL pointer dereference when parsing certain archives that have malformed extended headers.

The bug was discovered 01/02/2019. The weakness was released 03/22/2019 (Website). The advisory is shared at lists.opensuse.org. This vulnerability is known as CVE-2019-9923 since 03/22/2019. The attack can be launched remotely. The exploitation doesn't need any form of authentication. It demands that the victim is doing some kind of user interaction. Technical details are known, but no exploit is available.

The vulnerability was handled as a non-public zero-day exploit for at least 79 days. During that time the estimated underground price was around $0-$5k. The commercial vulnerability scanner Qualys is able to test this issue with plugin 172328 (OpenSUSE Security Update for tar (openSUSE-SU-2019:1237-1)).

Upgrading to version 1.32 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at SecurityFocus (BID 106354†). Entry connected to this vulnerability is available at VDB-128430. Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Vendor

• GNU

Name

• tar

Version

• 1.0
• 1.1
• 1.2
• 1.3
• 1.4
• 1.5
• 1.6
• 1.7
• 1.8
• 1.9
• 1.10
• 1.11
• 1.12
• 1.13
• 1.14
• 1.15
• 1.16
• 1.17
• 1.18
• 1.19
• 1.20
• 1.21
• 1.22
• 1.23
• 1.24
• 1.25
• 1.26
• 1.27
• 1.28
• 1.29
• 1.30
• 1.31

License

• open-source

Website

• Vendor: https://www.gnu.org/

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CPE 2.2info

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Entryinfo

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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