Cisco ASA Clientless SSL VPN memory corruption

CVSS Meta Temp Score
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CTI Interest Score
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7.2$0-$5k0.00

Summaryinfo

A vulnerability was found in Cisco ASA and classified as critical. Affected is an unknown function of the component Clientless SSL VPN. The manipulation results in memory corruption. This vulnerability is cataloged as CVE-2017-3807. The attack may be launched remotely. Furthermore, there is an exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, was found in Cisco ASA (Firewall Software) (the affected version is unknown). Affected is an unknown code of the component Clientless SSL VPN. The manipulation with an unknown input leads to a memory corruption vulnerability. CWE is classifying the issue as CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. This is going to have an impact on confidentiality, integrity, and availability.

The bug was discovered 02/08/2017. The weakness was shared 02/08/2017 by Oliver Chang with Google Project Zero as cisco-sa-20170208-asa as confirmed advisory (Website). The advisory is shared for download at tools.cisco.com. The vendor cooperated in the coordination of the public release. This vulnerability is traded as CVE-2017-3807 since 12/21/2016. It is possible to launch the attack remotely. A authentication is needed for exploitation. Technical details are unknown but a public exploit is available. The advisory points out:

A vulnerability in Common Internet Filesystem (CIFS) code in the Clientless SSL VPN functionality of Cisco ASA Software could allow an authenticated, remote attacker to cause a heap overflow. The vulnerability is due to insufficient validation of user supplied input. An attacker could exploit this vulnerability by sending a crafted URL to the affected system. An exploit could allow the remote attacker to cause a reload of the affected system or potentially execute code.

After 1 weeks, there has been an exploit disclosed. The exploit is shared for download at exploit-db.com. It is declared as proof-of-concept. As 0-day the estimated underground price was around $25k-$100k. The vulnerability scanner Nessus provides a plugin with the ID 97211 (Cisco ASA Clientless SSL VPN Functionality CIFS RCE (cisco-sa-20170208-asa)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family CISCO and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 316074 (Cisco ASA Clientless SSL VPN CIFS Heap Overflow Vulnerability (cisco-sa-20170208-asa)). The advisory illustrates:

Only traffic directed to the affected system can be used to exploit this vulnerability. This vulnerability affects systems configured in routed firewall mode only and in single or multiple context mode. This vulnerability can be triggered by IPv4 or IPv6 traffic. A valid TCP connection is needed to perform the attack. The attacker needs to have valid credentials to log in to the Clientless SSL VPN portal.

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

The vulnerability is also documented in the databases at Exploit-DB (41369), Tenable (97211), SecurityFocus (BID 96161†) and SecurityTracker (ID 1037797†). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.6
VulDB Meta Temp Score: 7.2

VulDB Base Score: 6.3
VulDB Temp Score: 5.7
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 8.8
NVD Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
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Exploitinginfo

Class: Memory corruption
CWE: CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Access: Public
Status: Proof-of-Concept
Download: 🔍

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 97211
Nessus Name: Cisco ASA Clientless SSL VPN Functionality CIFS RCE (cisco-sa-20170208-asa)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 800316
OpenVAS Name: Cisco ASA Clientless SSL VPN CIFS Heap Overflow Vulnerability
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Exploit-DB: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
Exposure Time: 🔍
Exploit Delay Time: 🔍

Timelineinfo

12/21/2016 🔍
02/08/2017 +49 days 🔍
02/08/2017 +0 days 🔍
02/08/2017 +0 days 🔍
02/08/2017 +0 days 🔍
02/08/2017 +0 days 🔍
02/09/2017 +1 days 🔍
02/09/2017 +0 days 🔍
02/15/2017 +6 days 🔍
02/15/2017 +0 days 🔍
02/16/2017 +1 days 🔍
08/28/2024 +2750 days 🔍

Sourcesinfo

Vendor: cisco.com

Advisory: cisco-sa-20170208-asa
Researcher: Oliver Chang
Organization: Google Project Zero
Status: Confirmed
Confirmation: 🔍
Coordinated: 🔍

CVE: CVE-2017-3807 (🔍)
GCVE (CVE): GCVE-0-2017-3807
GCVE (VulDB): GCVE-100-96744
SecurityFocus: 96161 - Cisco Adaptive Security Appliance Software Software CVE-2017-3807 Heap Buffer Overflow Vulnerability
OSVDB: - CVE-2017-3807 - Cisco - ASA Software - Heap Overflow Issue
SecurityTracker: 1037797

scip Labs: https://www.scip.ch/en/?labs.20161013

Entryinfo

Created: 02/09/2017 09:31
Updated: 08/28/2024 18:03
Changes: 02/09/2017 09:31 (86), 08/15/2020 16:11 (7), 11/12/2022 10:56 (3), 07/13/2024 17:02 (15), 08/28/2024 18:03 (2)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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