Ghostscript up to 9.20 psi/zht2.c .sethalftone5 type conversion

CVSS Meta Temp Score
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CTI Interest Score
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6.9$0-$5k0.00

Summaryinfo

A vulnerability classified as critical has been found in Ghostscript up to 9.20. This impacts the function .sethalftone5 of the file psi/zht2.c. This manipulation causes type conversion. The identification of this vulnerability is CVE-2016-8602. It is possible to initiate the attack remotely. There is no exploit available. It is suggested to install a patch to address this issue.

Detailsinfo

A vulnerability was found in Ghostscript up to 9.20 (Document Processing Software). It has been declared as critical. Affected by this vulnerability is the function .sethalftone5 of the file psi/zht2.c. The manipulation with an unknown input leads to a type conversion vulnerability. The CWE definition for the vulnerability is CWE-704. The product does not correctly convert an object, resource, or structure from one type to a different type. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

The .sethalftone5 function in psi/zht2.c in Ghostscript before 9.21 allows remote attackers to cause a denial of service (application crash) or possibly execute arbitrary code via a crafted Postscript document that calls .sethalftone5 with an empty operand stack.

The bug was discovered 10/05/2016. The weakness was shared 04/14/2017 by Tavis Ormandy (oss-sec). The advisory is shared at openwall.com. This vulnerability is known as CVE-2016-8602 since 10/11/2016. 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 97 days. During that time the estimated underground price was around $0-$5k. The vulnerability scanner Nessus provides a plugin with the ID 96395 (Amazon Linux AMI : ghostscript (ALAS-2017-784)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Amazon Linux Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 175860 (Debian Security Update for ghostscript (DSA 3691-1)).

Upgrading to version 9.21 eliminates this vulnerability. Applying a patch is able to eliminate this problem. The bugfix is ready for download at git.ghostscript.com. The best possible mitigation is suggested to be patching the affected component. A possible mitigation has been published even before and not after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Tenable (96395) and SecurityFocus (BID 95311†). The entries VDB-101645, VDB-101647 and VDB-104944 are related to this item. Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.0
VulDB Meta Temp Score: 6.9

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.8
NVD Vector: 🔍

CVSSv2info

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

NVD Base Score: 🔍

Exploitinginfo

Class: Type conversion
CWE: CWE-704
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: 96395
Nessus Name: Amazon Linux AMI : ghostscript (ALAS-2017-784)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 703691
OpenVAS Name: Debian Security Advisory DSA 3691-1 (ghostscript - security update)
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔍

Upgrade: Ghostscript 9.21
Patch: git.ghostscript.com

Timelineinfo

10/05/2016 🔍
10/08/2016 +3 days 🔍
10/11/2016 +3 days 🔍
01/10/2017 +91 days 🔍
01/11/2017 +1 days 🔍
04/14/2017 +93 days 🔍
04/14/2017 +0 days 🔍
04/15/2017 +1 days 🔍
11/29/2022 +2054 days 🔍

Sourcesinfo

Advisory: RHSA-2017:0013
Researcher: Tavis Ormandy
Status: Not defined
Confirmation: 🔍

CVE: CVE-2016-8602 (🔍)
GCVE (CVE): GCVE-0-2016-8602
GCVE (VulDB): GCVE-100-99889

OVAL: 🔍

SecurityFocus: 95311 - Ghostscript 'psi/zht2.c' NULL Pointer Dereference Remote Code Execution Vulnerability
OSVDB: - CVE-2016-8602 - Ghostscript - Denial of Service Issue

See also: 🔍

Entryinfo

Created: 04/15/2017 15:30
Updated: 11/29/2022 14:09
Changes: 04/15/2017 15:30 (81), 08/31/2020 14:16 (3), 11/29/2022 14:09 (4)
Complete: 🔍
Cache ID: 216:361:103

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