VDB-100399 · CVE-2017-3793 · BID 97923

Cisco ASA up to 8.7/9.6 TCP Normalizer resource management

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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4.7$0-$5k0.00

Summaryinfo

A vulnerability was found in Cisco ASA up to 8.7/9.6. It has been classified as problematic. This affects an unknown part of the component TCP Normalizer. This manipulation causes resource management. The identification of this vulnerability is CVE-2017-3793. It is possible to initiate the attack remotely. There is no exploit available.

Detailsinfo

A vulnerability has been found in Cisco ASA up to 8.7/9.6 (Firewall Software) and classified as problematic. Affected by this vulnerability is an unknown code block of the component TCP Normalizer. The manipulation with an unknown input leads to a resource management vulnerability. The CWE definition for the vulnerability is CWE-399. As an impact it is known to affect availability. The summary by CVE is:

A vulnerability in the TCP normalizer of Cisco Adaptive Security Appliance (ASA) Software (8.0 through 8.7 and 9.0 through 9.6) and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause Cisco ASA and FTD to drop any further incoming traffic on all interfaces, resulting in a denial of service (DoS) condition. The vulnerability is due to improper limitation of the global out-of-order TCP queue for specific block sizes. An attacker could exploit this vulnerability by sending a large number of unique permitted TCP connections with out-of-order segments. An exploit could allow the attacker to exhaust available blocks in the global out-of-order TCP queue, causing the dropping of any further incoming traffic on all interfaces and resulting in a DoS condition. Cisco Bug IDs: CSCvb46321.

The bug was discovered 04/19/2017. The weakness was shared 04/20/2017 with Cisco as cisco-sa-20170419-asa-norm as confirmed advisory (Website). It is possible to read the advisory at tools.cisco.com. This vulnerability is known as CVE-2017-3793 since 12/21/2016. The attack can be launched remotely. The exploitation doesn't need any form of authentication. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 08/28/2024).

The vulnerability was handled as a non-public zero-day exploit for at least 1 days. During that time the estimated underground price was around $5k-$25k. The commercial vulnerability scanner Qualys is able to test this issue with plugin 316110 (Cisco ASA Software TCP Normalizer Denial of Service Vulnerability (cisco-sa-20170419-asa-norm)).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at SecurityFocus (BID 97923†). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.7
VulDB Meta Temp Score: 4.7

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

NVD Base Score: 4.0
NVD Vector: 🔍

CVSSv2info

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

NVD Base Score: 🔍

Exploitinginfo

Class: Resource management
CWE: CWE-399 / CWE-404
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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OpenVAS ID: 800316
OpenVAS Name: Cisco ASA Software TCP Normalizer Denial of Service Vulnerability
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔍

Timelineinfo

12/21/2016 🔍
04/19/2017 +119 days 🔍
04/19/2017 +0 days 🔍
04/20/2017 +1 days 🔍
04/20/2017 +0 days 🔍
04/21/2017 +1 days 🔍
08/28/2024 +2686 days 🔍

Sourcesinfo

Vendor: cisco.com

Advisory: cisco-sa-20170419-asa-norm
Researcher: Cisco
Organization: Cisco
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2017-3793 (🔍)
GCVE (CVE): GCVE-0-2017-3793
GCVE (VulDB): GCVE-100-100399

OVAL: 🔍

SecurityFocus: 97923 - Cisco ASA Software and FTD Software CVE-2017-3793 Denial of Service Vulnerability
OSVDB: - CVE-2017-3793 - Cisco - ASA - Denial of Service Issue
SecurityTracker: 1038329

Entryinfo

Created: 04/21/2017 10:10
Updated: 08/28/2024 20:02
Changes: 04/21/2017 10:10 (67), 09/19/2020 09:21 (6), 12/21/2020 10:30 (2), 12/21/2020 10:36 (1), 08/28/2024 20:02 (16)
Complete: 🔍
Cache ID: 216::103

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