Bug 2538827 (CVE-2026-83602)

Summary: CVE-2026-83602 netdata: Netdata: Denial of Service via unauthenticated API requests
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
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Priority: high    
Version: unspecifiedKeywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in Netdata, an open-source observability tool. An unauthenticated remote attacker can bypass IP allowlist restrictions by sending PUT requests to the `/api/v3/settings` endpoint. This allows the attacker to write arbitrary data to a settings file, potentially leading to a Denial of Service (DoS) by consuming disk space. While the file does not control security policy, repeated writes can impact system availability.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Bug Depends On: 2539379    
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Description OSIDB Bzimport 2026-09-22 20:48:31 UTC
Netdata is an open source observability tool. From 2.0.0 until 2.11.0, Netdata registers /api/v3/settings in src/web/api/v3/web_api_v3.c with HTTP_ACL_NOCHECK and HTTP_ACCESS_ANONYMOUS_DATA, causing unauthenticated PUT requests handled by src/web/api/v3/api_v3_settings.c to bypass operator-configured allow dashboard from IP restrictions. A network-reachable caller can persist attacker-controlled JSON in {varlib}/settings/default.json, manipulate its version counter, and use repeated near-20 MiB writes to consume disk space, although the file does not control collection or security policy. This vulnerability is fixed in 2.11.0.