VDB-100634 · CVE-2017-8294 · BID 98072

YARA 3.5.0 Regex libyara/re.c yr_re_exec out-of-bounds

CVSS Meta Temp Score
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CTI Interest Score
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6.1$0-$5k0.00

A vulnerability was found in YARA 3.5.0 and classified as problematic. Affected by this issue is the function yr_re_exec of the file libyara/re.c of the component Regex Handler. The manipulation with an unknown input leads to a out-of-bounds vulnerability. Using CWE to declare the problem leads to CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. Impacted is availability. CVE summarizes:

libyara/re.c in the regex component in YARA 3.5.0 allows remote attackers to cause a denial of service (out-of-bounds read and application crash) via a crafted rule that is mishandled in the yr_re_exec function.

The bug was discovered 04/27/2017. The weakness was shared 04/27/2017 (GitHub Repository). The advisory is available at github.com. This vulnerability is handled as CVE-2017-8294 since 04/27/2017. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. Technical details are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 99743 (Fedora 25 : yara (2017-11ac1e31eb)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Fedora Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 276651 (Fedora Security Update for yara (FEDORA-2017-11ac1e31eb)).

Upgrading eliminates this vulnerability. A possible mitigation has been published 2 days after the disclosure of the vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (99743).

Productinfo

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Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB CVSS-B Score: 🔍
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CVSSv3info

VulDB Meta Base Score: 6.4
VulDB Meta Temp Score: 6.1

VulDB Base Score: 5.3
VulDB Temp Score: 4.7
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.5
NVD Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
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Exploitinginfo

Class: Out-of-bounds
CWE: CWE-125 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

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Price Prediction: 🔍
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Nessus ID: 99743
Nessus Name: Fedora 25 : yara (2017-11ac1e31eb)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 867773
OpenVAS Name: Fedora Update for yara FEDORA-2017-9941306740
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

Interest: 🔍
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Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

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Patch: github.com

Timelineinfo

04/27/2017 🔍
04/27/2017 +0 days 🔍
04/27/2017 +0 days 🔍
04/27/2017 +0 days 🔍
04/27/2017 +0 days 🔍
04/28/2017 +1 days 🔍
04/29/2017 +1 days 🔍
05/01/2017 +2 days 🔍
12/02/2022 +2041 days 🔍

Sourcesinfo

Advisory: FEDORA-2017-11ac1e31eb
Status: Not defined
Confirmation: 🔍

CVE: CVE-2017-8294 (🔍)
SecurityFocus: 98072 - YARA CVE-2017-8294 Denial of Service Vulnerability
OSVDB: - CVE-2017-8294 - YARA - Denial of Service Issue

Entryinfo

Created: 04/28/2017 20:16
Updated: 12/02/2022 12:09
Changes: 04/28/2017 20:16 (81), 12/02/2022 12:01 (5), 12/02/2022 12:09 (1)
Complete: 🔍
Cache ID: 3:E43:103

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