CyberSecBulletin
CVE-2022-43755NVD status: Modified

Rancher: Insufficient Entropy

CVE-2022-43755 is a critical-severity insufficient entropy vulnerability in Rancher from SUSE, with a CVSS 3.1 base score of 9.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists version 2.6.10 as the first without the flaw, so updating Rancher to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 1.72% chance of exploitation within 30 days, higher than 78% of scored CVEs.

Patch this week

Critical severity: a successful attack would have severe impact.

What to do

  1. Update Rancher to 2.6.10 or a later version.
  2. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
SUSERancherRancher up to, but not including, 2.6.102.6.10

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
NoneNo account or login is needed.
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:N/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.17.1HighCNA (suse.de)
CVSS 3.19.8CriticalNVD

Official description

A Insufficient Entropy vulnerability in SUSE Rancher allows attackers that gained knowledge of the cattle-token to continue abusing this even after the token was renewed. This issue affects: SUSE Rancher Rancher versions prior to 2.6.10; Rancher versions prior to 2.7.1.

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

The underlying weakness: Insufficient Entropy

The product uses an algorithm or scheme that produces insufficient entropy, leaving patterns or clusters of values that are more likely to occur than others.

How developers prevent this class of flaw

  • Determine the necessary entropy to adequately provide for randomness and predictability. This can be achieved by increasing the number of bits of objects such as keys and seeds.

More Insufficient Entropy vulnerabilities (CWE-331)

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

Patches and release notes

Other vulnerabilities in Rancher

All Rancher vulnerabilities

Recent Insufficient Entropy vulnerabilities

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