Cisco Linksys Router E4200/EA2700/EA3500/EA4500 backdoor

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.7$0-$5k0.00

A vulnerability, which was classified as critical, has been found in Cisco Linksys Router E4200/EA2700/EA3500/EA4500 (Router Operating System). Affected by this issue is some unknown functionality. The manipulation with an unknown input leads to a backdoor vulnerability. Using CWE to declare the problem leads to CWE-912. The product contains functionality that is not documented, not part of the specification, and not accessible through an interface or command sequence that is obvious to the product's users or administrators. Impacted is confidentiality, integrity, and availability.

The weakness was released 07/01/2013 by Kyle Lovett as Update: Linksys EA2700, EA3500, E4200v2, EA4500 Unspecified unauthenticated remote access as confirmed mailinglist post (Bugtraq). The advisory is available at seclists.org. The vendor was not involved in the coordination of the public release. This vulnerability is handled as CVE-2013-5122 since 08/14/2013. The attack may be launched remotely. No form of authentication is required for exploitation. Technical details are unknown but a public exploit is available. This vulnerability is assigned to T1588.001 by the MITRE ATT&CK project.

A public exploit has been developed by phrag in HTTP GET Request and been published 2 years after the advisory. The exploit is available at phra.gs. It is declared as proof-of-concept. As 0-day the estimated underground price was around $5k-$25k. The code used by the exploit is:

curl -i http://192.168.2.10:8083
The advisory illustrates:
A HTTP GET request on port 8083 without authentication returns 200 OK and has full admin privileges

Upgrading to version 2.1.39.145204 eliminates this vulnerability.Addressing this vulnerability is possible by firewalling tcp/8083 (us-srv). The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the vulnerability database at X-Force (86480). seclists.org is providing further details. Entries connected to this vulnerability are available at VDB-5620, VDB-7608 and VDB-12362.

Affected

  • Linksys EA2700 1.0.14
  • Linksys E4200 2.0.36
  • Linksys EA3500 1.0.30
  • Linksys EA4500 2.0.36

Productinfo

Type

Vendor

Name

Version

License

Support

  • end of life (old version)

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB CVSS-B Score: 🔍
VulDB CVSS-BT Score: 🔍
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.5
VulDB Meta Temp Score: 8.2

VulDB Base Score: 7.3
VulDB Temp Score: 6.6
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 9.8
NVD Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
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Exploitinginfo

Class: Backdoor
CWE: CWE-912
CAPEC: 🔍
ATT&CK: 🔍

Local: No
Remote: Yes

Availability: 🔍
Access: Public
Status: Proof-of-Concept
Author: phrag
Programming Language: 🔍
Download: 🔍

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍
Exploit Delay Time: 🔍

Upgrade: Linksys Router 2.1.39.145204
Firewalling: 🔍

Timelineinfo

07/01/2013 🔍
07/01/2013 +0 days 🔍
07/04/2013 +3 days 🔍
08/14/2013 +41 days 🔍
04/10/2014 +239 days 🔍
06/04/2014 +55 days 🔍
05/17/2021 +2539 days 🔍

Sourcesinfo

Vendor: cisco.com

Advisory: Update: Linksys EA2700, EA3500, E4200v2, EA4500 Unspecified unauthenticated remote access
Researcher: Kyle Lovett
Status: Confirmed

CVE: CVE-2013-5122 (🔍)
X-Force: 86480
SecurityTracker: 1029769
Vulnerability Center: 43987 - Linksys Routers Remote Security Bypass Vulnerability in Administrative Console, Critical
OSVDB: 94768 - Cisco Linksys Multiple Router Unspecified Unauthenticated Remote Administration Access

scip Labs: https://www.scip.ch/en/?labs.20161013
Misc.: 🔍
See also: 🔍

Entryinfo

Created: 07/04/2013 12:33 PM
Updated: 05/17/2021 03:24 PM
Changes: 07/04/2013 12:33 PM (58), 07/09/2015 11:47 AM (9), 05/17/2021 03:18 PM (3), 05/17/2021 03:24 PM (18)
Complete: 🔍
Committer:
Cache ID: 44:AB4:40

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