CyberSecBulletin
CVE-2023-20195NVD status: Modified

Cisco Identity Services Engine Software: Unrestricted Upload of File with Dangerous Type

CVE-2023-20195 is a high-severity unrestricted upload of file with dangerous type vulnerability in Cisco Identity Services Engine Software from Cisco, with a CVSS 3.1 base score of 7.2 out of 10. It can be exploited remotely over the network by an attacker with administrator privileges, without any action from a user. Affected Cisco Identity Services Engine Software versions: 2.6.0; 2.6.0 p1; 2.6.0 p2, and others listed below. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.76% chance of exploitation within 30 days, higher than 56% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Check which version of Cisco Identity Services Engine Software you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on sec.cloudapps.cisco.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
CiscoCisco Identity Services Engine Software2.6.0; 2.6.0 p1; 2.6.0 p2; 2.6.0 p3; 2.6.0 p5; 2.6.0 p6; 2.6.0 p7; 2.6.0 p8; and 31 more rangesNot stated
CiscoIdentity Services Engine2.7.0; 3.0.0; 3.1; 3.2Not stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
HighAdministrator-level access is required first.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.14.7MediumCNA (cisco.com)
CVSS 3.17.2HighNVD

Official description

Two vulnerabilities in Cisco ISE could allow an authenticated, remote attacker to upload arbitrary files to an affected device. To exploit these vulnerabilities, an attacker must have valid Administrator credentials on the affected device. These vulnerabilities are due to improper validation of files that are uploaded to the web-based management interface. An attacker could exploit these vulnerabilities by uploading a crafted file to an affected device. A successful exploit could allow the attacker to store malicious files in specific directories on the device. The attacker could later use those files to conduct additional attacks, including executing arbitrary code on the affected device with root privileges.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Unrestricted Upload of File with Dangerous Type

The product allows the upload or transfer of dangerous file types that are automatically processed within its environment.

How developers prevent this class of flaw

  • Generate a new, unique filename for an uploaded file instead of using the user-supplied filename, so that no external input is used at all.
  • When the set of acceptable objects, such as filenames or URLs, is limited or known, create a mapping from a set of fixed input values (such as numeric IDs) to the actual filenames or URLs, and reject all other inputs.
  • Consider storing the uploaded files outside of the web document root entirely. Then, use other mechanisms to deliver the files dynamically.

More Unrestricted Upload of File with Dangerous Type vulnerabilities (CWE-434)

Timeline

  1. CVE record published.
  2. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in Cisco Identity Services Engine Software

All Cisco Identity Services Engine Software vulnerabilities

Recent Unrestricted Upload of File with Dangerous Type vulnerabilities

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