Apache Storm Nimbus: Blobstore Authorization Bypass via Rebalance Configuration Overrides
Summary
| CVE | CVE-2026-82432 |
|---|---|
| State | PUBLISHED |
| Assigner | apache |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-09-14 15:17:10 UTC |
| Updated | 2026-09-14 20:58:48 UTC |
| Description | Description Nimbus validated `topology.blobstore.map` against the calling subject at submission time only. The rebalance operation accepts configuration overrides and stripped a small set of keys from them, but never re-ran that validation, so a caller authorised to rebalance a topology could introduce a blobstore map entry naming a blob whose ACL does not grant them access. Supervisors localise whatever key the map names, placing the blob's contents into the topology's working directory. The same advisory covers `listBlobs`, which performed no authorization check and passed no subject, unlike the neighbouring `getBlobMeta` and `beginBlobDownload` operations. It therefore returned every key in the blobstore to any caller able to reach the Nimbus Thrift port, which provides the key names that make the above practical. On its own the disclosure is metadata only. Mitigation Upgrade to 3.1.0, where rebalance configuration overrides are validated exactly as submission-time configuration is, against the rebalancing caller, and where `listBlobs` applies the configured authorization. Users who cannot upgrade immediately should restrict rebalance rights to trusted principals, keeping in mind that membership of a topology's `topology.users` or `topology.groups` confers them. Credit The ASF -- found using Claude agents to study the security of open-source projects, validated and reported by Apache Storm. |
Risk And Classification
Primary CVSS: v3.1 8.1 HIGH from ADP
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
EPSS: 0.003450000 probability, percentile 0.277040000 (date 2026-09-15)
Problem Types: CWE-863 | CWE-863 CWE-863 Incorrect Authorization
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | ADP | DECLARED | 8.1 | HIGH | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N |
| 3.1 | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | Secondary | 8.1 | HIGH | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N |
CVSS v3.1 Breakdown
Attack Vector
NetworkAttack Complexity
LowPrivileges Required
LowUser Interaction
NoneScope
UnchangedConfidentiality
HighIntegrity
HighAvailability
NoneCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Apache Software Foundation | Apache Storm Nimbus | affected 3.0.0 3.1.0 semver | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| lists.apache.org/thread/psy1gj77jhf9y3lhph9yz4f5fovmkz7b | [email protected] | lists.apache.org | |
| www.openwall.com/lists/oss-security/2026/09/13/12 | af854a3a-2127-422b-91ae-364da2661108 | www.openwall.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
Vendor Comments And Credit
Discovery Credit
CNA: The ASF using Claude Agents (en)
There are currently no legacy QID mappings associated with this CVE.