CyberSecBulletin
CVE-2022-43760NVD status: Modified

Rancher: Improper Neutralization of Input During Web Page Generation

CVE-2022-43760 is a high-severity improper neutralization of input during web page generation vulnerability in Rancher from SUSE, with a CVSS 3.1 base score of 8.4 out of 10. It can be exploited remotely over the network by an attacker with administrator privileges, but only if a user takes part, for example by opening a link or file. The record lists versions < 2.6.13, < 2.7.4 as the first without the flaw, so updating Rancher to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.71% chance of exploitation within 30 days, higher than 54% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Rancher to < 2.6.13 or < 2.7.4, whichever matches your release line, or a later version.
  2. Read the advisory on bugzilla.suse.com for workarounds and exact fixed builds.
  3. Because the attack needs a user to take part, warn users about unexpected links and files related to this product until it is patched.

Affected products and versions

VendorProductAffected versionsFixed in
SUSERancher>= 2.6.0 up to, but not including, < 2.6.13; >= 2.7.0 up to, but not including, < 2.7.4< 2.6.13, < 2.7.4

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
RequiredA user must take an action such as opening a file or link.
Scope
ChangedThe attack can reach beyond the vulnerable component into other systems.
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:R/S:C/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.18.4HighCNA (suse.de)
CVSS 3.18.4HighNVD

Official description

An Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in SUSE Rancher allows users in some higher-privileged groups to to inject code that is executed within another user's browser, allowing the attacker to steal sensitive information, manipulate web content, or perform other malicious activities on behalf of the victims. This could result in a user with write access to the affected areas being able to act on behalf of an administrator, once an administrator opens the affected web page. This issue affects Rancher: from >= 2.6.0 before < 2.6.13, from >= 2.7.0 before < 2.7.4.

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

The underlying weakness: Improper Neutralization of Input During Web Page Generation

The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.

How developers prevent this class of flaw

  • Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. Examples of libraries and frameworks that make it easier to generate properly encoded output include Microsoft's Anti-XSS library, the OWASP ESAPI Encoding module, and Apache Wicket.
  • Understand all the potential areas where untrusted inputs can enter your software: parameters or arguments, cookies, anything read from the network, environment variables, reverse DNS lookups, query results, request headers, URL components, e-mail, files, filenames, databases, and any external systems that provide data to the application. Remember that such inputs may be obtained indirectly through API calls.
  • For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.

More Improper Neutralization of Input During Web Page Generation vulnerabilities (CWE-79)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in Rancher

All Rancher vulnerabilities

Recent Improper Neutralization of Input During Web Page Generation vulnerabilities

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