Cisco IOS/IOS XE L2TP Parser resource management

CVSS Meta Temp Score
CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.
Current Exploit Price (≈)
Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.
CTI Interest Score
Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
7.1$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as problematic, has been found in Cisco IOS and IOS XE. The affected element is an unknown function of the component L2TP Parser. Performing a manipulation results in resource management. This vulnerability is cataloged as CVE-2017-3857. It is possible to initiate the attack remotely. There is no exploit available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability classified as problematic has been found in Cisco IOS and IOS XE (Router Operating System). This affects an unknown functionality of the component L2TP Parser. The manipulation with an unknown input leads to a resource management vulnerability. CWE is classifying the issue as CWE-399. This is going to have an impact on availability. The summary by CVE is:

A vulnerability in the Layer 2 Tunneling Protocol (L2TP) parsing function of Cisco IOS (12.0 through 12.4 and 15.0 through 15.6) and Cisco IOS XE (3.1 through 3.18) could allow an unauthenticated, remote attacker to cause an affected device to reload. The vulnerability is due to insufficient validation of L2TP packets. An attacker could exploit this vulnerability by sending a crafted L2TP packet to an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a denial of service (DoS) condition. This vulnerability affects Cisco devices that are running a vulnerable release of Cisco IOS or Cisco IOS XE Software if the L2TP feature is enabled for the device and the device is configured as an L2TP Version 2 (L2TPv2) or L2TP Version 3 (L2TPv3) endpoint. By default, the L2TP feature is not enabled. Cisco Bug IDs: CSCuy82078.

The bug was discovered 03/22/2017. The weakness was shared 03/22/2017 with Cisco as cisco-sa-20170322-l2tp as confirmed advisory (Website). It is possible to read the advisory at tools.cisco.com. This vulnerability is uniquely identified as CVE-2017-3857 since 12/21/2016. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. The technical details are unknown and an exploit is not publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 99028 (Cisco IOS L2TP Parsing DoS (cisco-sa-20170322-l2tp)), 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 c. The commercial vulnerability scanner Qualys is able to test this issue with plugin 316101 (Cisco IOS and IOS XE Software Layer 2 Tunneling Protocol Denial of Service Vulnerability (cisco-sa-20170322-l2tp)).

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 Tenable (99028) and SecurityFocus (BID 97010†). The entry VDB-98382 is related to this item. Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Affected

  • Cisco IOS up to 12.4/15.6
  • Cisco IOS XE 3.1 up to 3.18

Productinfo

Type

Vendor

Name

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.1
VulDB Meta Temp Score: 7.1

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

Vendor Base Score (Cisco): 8.6
Vendor Vector (Cisco): 🔍

NVD Base Score: 7.5
NVD Vector: 🔍

CVSSv2info

AVACAuCIA
💳💳💳💳💳💳
💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
UnlockUnlockUnlockUnlockUnlockUnlock
UnlockUnlockUnlockUnlockUnlockUnlock
UnlockUnlockUnlockUnlockUnlockUnlock

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: 🔍

0-DayUnlockUnlockUnlockUnlock
TodayUnlockUnlockUnlockUnlock

Nessus ID: 99028
Nessus Name: Cisco IOS L2TP Parsing DoS (cisco-sa-20170322-l2tp)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 103403
OpenVAS Name: Cisco IOS XE Software Layer 2 Tunneling Protocol Denial of Service Vulnerability
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

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

Timelineinfo

12/21/2016 🔍
03/22/2017 +91 days 🔍
03/22/2017 +0 days 🔍
03/22/2017 +0 days 🔍
03/22/2017 +0 days 🔍
03/22/2017 +0 days 🔍
03/23/2017 +1 days 🔍
03/28/2017 +5 days 🔍
08/28/2024 +2710 days 🔍

Sourcesinfo

Vendor: cisco.com

Advisory: cisco-sa-20170322-l2tp
Organization: Cisco
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2017-3857 (🔍)
GCVE (CVE): GCVE-0-2017-3857
GCVE (VulDB): GCVE-100-98379

OVAL: 🔍

SecurityFocus: 97010 - Cisco IOS and IOS XE Software CVE-2017-3857 Denial of Service Vulnerability
OSVDB: - CVE-2017-3857 - Cisco - Multiple Products - Denial of Service Issue
SecurityTracker: 1038100

scip Labs: https://www.scip.ch/en/?labs.20150108
See also: 🔍

Entryinfo

Created: 03/23/2017 07:56
Updated: 08/28/2024 07:10
Changes: 03/23/2017 07:56 (83), 09/10/2020 22:20 (8), 11/14/2022 12:02 (3), 08/28/2024 07:10 (16)
Complete: 🔍
Cache ID: 216::103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Discussion

No comments yet. Languages: en.

Please log in to comment.

◂ PreviousOverviewNext ▸

Do you need the next level of professionalism?

Upgrade your account now!