High File handling

CVE-2026-87976 — Apache NiFi Registry: Improper Limitation of Pathname in Persisted Extension Bundles

Apache NiFi Registry 0.4.0 through 2.11.0 are subject to path manipulation when storing extension bundle content using group, artifact, and version coordinates from uploaded NAR manifests. The default file persistence provider used coordinates as filesystem path components without rejected parent-directory names, and the path-containment check compared an unnormalized resolved path. An authenticated user authorized to write and delete bundles in a bucket can upload a NAR with a crafted manifest resulting in file system operations outside of the file persistence directory. Upgrading to Apache NiFi Registry 2.12.0 is the recommended mitigation, which rejects parent-directory coordinates and requires a normalized path to remain a strict child of the storage root location.

Published Sep 16, 2026 · Updated Oct 15, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP · CNA: apache

Low

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.

How the score was calculated

EPSS 0.8% (30-day exploitation probability)+8
Technical severity (high)+6

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation

Not confirmed

Not in CISA KEV — an absence of record, not proof it is unexploited.

EPSS FIRST

0.79%

ahead of 55% of scored CVEs · Oct 15, 2026

Affects

Apache Software Foundation

Apache NiFi Registry and 1 more

CVSS base

8.1

High · 3 source(s)

CISA SSVC assessment CISA

Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.

Exploitation

None

none · proof-of-concept · active

Automatable

can an attacker script the kill-chain steps

Technical impact

Partial

partial · total control of the vulnerable component

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

Identify exposed assets running the affected vendor/product/version combinations (Apache Software Foundation Apache NiFi Registry, Apache Software Foundation Nifi).
No fix documented in the sources: reduce exposure and monitor the vendor advisory.
Search available logs for exploit probes matching the vulnerability class (file handling), errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

Vendor	Product	Versions	Status	Source
Apache Software Foundation	Apache NiFi Registry	≥ 0.4.0 and ≤ 2.11.0	Vulnerable	CVE Program (cve.org) e CISA ADP
Apache Software Foundation	Nifi	≥ 0.4.0 and < 2.12.0	Vulnerable	NIST National Vulnerability Database

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector

Network

Attack complexity

Low

Privileges required

Low

User interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

High

Availability

High

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

Score	Version	Severity	Expl.	Impact	Scored by
7.2	CVSS 4.0	High	—	—	security@apache.org via NIST National Vulnerability Database
7.2	CVSS 4.0	High	—	—	apache via CVE Program (cve.org) e CISA ADP
8.1	CVSS 3.1	High	2.8	5.2	nvd@nist.gov via NIST National Vulnerability Database

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H (score shown at the top: nvd@nist.gov)

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-22 · Path Traversal

Other CVEs with this weakness →

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
Monitor file creation in web directories and paths with traversal sequences (../).

web/proxy/WAF logsnetwork IDS/IPSfile integrity (FIM)endpoint telemetry (EDR)

Timeline

What happened to this CVE, newest first.

2026
Affected products added · apache software foundation/apache nifi registry
Oct 15, 2026 · CVE Program (cve.org) e CISA ADP
SSVC assessment updated
Oct 15, 2026 · CVE Program (cve.org) e CISA ADP
Record published
Oct 15, 2026
CVSS changed · 8.1
Oct 15, 2026 · NIST National Vulnerability Database
Source status changed · → Analyzed
Oct 15, 2026 · NIST National Vulnerability Database
Record created in this database
Oct 15, 2026 · NIST National Vulnerability Database
CVE published
Sep 16, 2026 · apache

Source activity

Repeated readings are counted rather than listed.

1× Official description updated · Oct 15, 2026 – Oct 15, 2026

References

2 on the record

lists.apache.org/thread/kw89toml5zq20ry3279mx7y184vrlb8x
Mailing List, Vendor Advisory, vendor-advisory, NIST National Vulnerability Database
www.openwall.com/lists/oss-security/2026/09/16/11
Mailing List, Third Party Advisory, NIST National Vulnerability Database

Elsewhere on this site

Apache Software Foundation
every CVE for this vendor

File handling
same class

CWE-22
other pages naming this weakness

Related CVEs (same products)

High CVE-2026-86089 Apache NiFi: Missing Process Group Authorization for Connector Migration Sep 16, 2026
Medium CVE-2026-82561 Apache NiFi: Missing Authorization for Components Referenced in Flow Update Methods Sep 16, 2026
Medium CVE-2026-81866 Apache NiFi: Missing Authorization for Assets and Secrets Referenced by Connector Configuration Sep 16, 2026
High CVE-2026-70469 Apache NiFi: Improper Handling of Case Sensitivity for Content-Encoding in HTTP Requests Sep 16, 2026
High CVE-2026-68981 Apache NiFi: Uncontrolled Resource Consumption through Decompression of HTTP Requests Aug 3, 2026
Critical CVE-2026-68980 Apache NiFi: Authorization Bypass for Parameter Context Asset Deletion Aug 3, 2026

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

No fixed version, patch or mitigation documented.
No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2026-87976 is "Apache NiFi Registry: Improper Limitation of Pathname in Persisted Extension Bundles", rated High. It affects Apache NiFi Registry (Apache Software Foundation); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 8.1 describes technical severity. EPSS 0.79% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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