CyberSecBulletin
CVE-2026-8100NVD status: Deferred

Chef360: Relative Path Traversal

CVE-2026-8100 is a high-severity relative path traversal vulnerability in Chef360 from Progress Chef, with a CVSS 4.0 base score of 8.6 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. The record lists version 1.7.1 as the first without the flaw, so updating Chef360 to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.55% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Chef360 to 1.7.1 or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
Progress ChefChef360before 1.7.11.7.1

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.
Attack requirements
NoneThe attack does not depend on a particular deployment or configuration.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Confidentiality (vulnerable system)
HighSerious loss of confidentiality on the vulnerable system.
Integrity (vulnerable system)
HighSerious loss of integrity on the vulnerable system.
Availability (vulnerable system)
HighSerious loss of availability on the vulnerable system.
Confidentiality (other systems)
HighSerious loss of confidentiality on systems beyond the vulnerable one.
Integrity (other systems)
HighSerious loss of integrity on systems beyond the vulnerable one.
Availability (other systems)
HighSerious loss of availability on systems beyond the vulnerable one.

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:N/AU:Y/R:X/V:X/RE:M/U:X. Scored by CNA (progress.com).

Official description

Impact A security issue has been identified in Chef 360 that could allow unauthorized access to protected API endpoints under specific conditions. This issue is due to improper handling of URL-encoded paths during request processing. In certain scenarios, an authenticated request may bypass standard access controls gaining additional privileges, potentially allowing access to API endpoints that are intended to be restricted to higher-permissioned roles. The impact is limited to environments where the affected request patterns can be triggered and depends on specific deployment configuration and access controls in place. Resolution The issue has been addressed through product updates that improve request validation and enforce strict path normalization before authorization checks. Customers are advised to update to the latest available version containing the fix, version 1.7.1 or later.

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

The underlying weakness: Relative Path Traversal

The product uses external input to construct a pathname that should be within a restricted directory, but it does not properly neutralize sequences such as.. that can resolve to a location that is outside of that directory.

How developers prevent this class of flaw

  • Use an application firewall that can detect attacks against this weakness. It can be beneficial in cases in which the code cannot be fixed (because it is controlled by a third party), as an emergency prevention measure while more comprehensive software assurance measures are applied, or to provide defense in depth.

More Relative Path Traversal vulnerabilities (CWE-23)

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

Recent Relative Path Traversal vulnerabilities

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