CVE-2026-82561
As a result of the missing authorization, an authenticated user with write access to a Process Group could supply a flow definition that modifies or removes components in descendant Process Groups protected by more restrictive access policies, and could…
Does this matter?
Lower severity and a low EPSS score (0.48%). Track it; it rarely justifies an emergency change on its own.
Description
Apache NiFi 1.5.0 through 2.11.0 provide REST API methods that replace the entire contents of a Process Group using a client-supplied flow definition, covering Process Group flow replacement together with versioned flow update and rebase operations. Framework authorization for these methods was limited to read and write privileges on the Process Group itself, unlike the corresponding asynchronous update request methods, which also authorize the components encapsulated in the Process Group along with referenced Controller Services, Parameter Contexts, and Parameter Providers. As a result of the missing authorization, an authenticated user with write access to a Process Group could supply a flow definition that modifies or removes components in descendant Process Groups protected by more restrictive access policies, and could bind components to Controller Services and Parameter Contexts without authorization for those referenced components. Existing verification checks limited the impact to stopped components, and the issue applies only to deployments that use component-level authorization policies, because the framework enforces write permissions as the security boundary. Upgrading to Apache NiFi 2.12.0 is the recommended mitigation, which applies consistent reference resolution and component authorization across Process Group replacement and versioned flow update methods
- CVSS 4.0
- 5.9 MEDIUMCVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:L/VI:H/VA:L/SC:L/SI:L/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
- EPSS
- 0.48% probability · 41th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-862
- Affected
- apache/nifi
- Source
- security@apache.org
EPSS 0.5% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://lists.apache.org/thread/opk7l8wqvnl85qxlzj3dnxp6qbk27lwmMailing List, Vendor Advisory
- http://www.openwall.com/lists/oss-security/2026/09/16/9Mailing List, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.