CVE-2026-59739 (GCVE-0-2026-59739)
Vulnerability from cvelistv5 – Published: 2026-09-16 09:26 – Updated: 2026-09-16 09:26
VLAI
EPSS
VEX
Title
Apache ZooKeeper: Information disclosure via SetWatches reconnect replay
Summary
Information disclosure via SetWatches reconnect replay in Apache ZooKeeper due to missing ACL check. An attacker can discover ACL-restricted paths by registering exists-watches on non-existent paths, then reconnecting after the paths are created with restricted ACLs. Issue is caused by incomplete fix for CVE-2024-23944 (ZOOKEEPER-4799). The fix added ACL checking to WatchManager.triggerWatch(). However, DataTree.setWatches() — the SetWatches/SetWatches2 reconnect replay handler — still calls watcher.process(event) with null ACL, bypassing the check entirely. It's important to note that only the path is exposed by this vulnerability, not the data of znode, but since znode path can contain sensitive information like user name or login ID, this issue is potentially critical.
Users are recommended to upgrade to version 3.9.6, 3.8.7 which fixes the issue.
Severity
No CVSS data available.
CWE
- CWE-862 - Missing Authorization
Assigner
References
1 reference
| URL | Tags |
|---|---|
| https://lists.apache.org/thread/v0lrwsbdxvx6w67p3… | vendor-advisory |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Apache Software Foundation | Apache ZooKeeper |
Affected:
3.9.0 , ≤ 3.9.5
(maven)
Affected: 3.8.0 , ≤ 3.8.6 (semver) |
guessed |
{
"containers": {
"cna": {
"affected": [
{
"collectionURL": "https://repo.maven.apache.org/maven2",
"defaultStatus": "unaffected",
"packageName": "org.apache.zookeeper:zookeeper",
"packageURL": "pkg:maven/org.apache.zookeeper/zookeeper",
"product": "Apache ZooKeeper",
"vendor": "Apache Software Foundation",
"versions": [
{
"lessThanOrEqual": "3.9.5",
"status": "affected",
"version": "3.9.0",
"versionType": "maven"
},
{
"lessThanOrEqual": "3.8.6",
"status": "affected",
"version": "3.8.0",
"versionType": "semver"
}
]
}
],
"credits": [
{
"lang": "en",
"type": "reporter",
"value": "NGUYEN HONG QUAN \u003chongquanvp11@gmail.com\u003e"
},
{
"lang": "en",
"type": "reporter",
"value": "n0mi1k \u003cnomilksec@gmail.com\u003e"
}
],
"descriptions": [
{
"lang": "en",
"supportingMedia": [
{
"base64": false,
"type": "text/html",
"value": "Information disclosure via SetWatches reconnect replay in Apache ZooKeeper due to missing ACL check.\u0026nbsp;An attacker can discover ACL-restricted paths by registering exists-watches on non-existent paths, then reconnecting after the paths are created with restricted ACLs. Issue is caused by incomplete fix for\u0026nbsp;CVE-2024-23944 (ZOOKEEPER-4799).\u0026nbsp;The fix added ACL checking to WatchManager.triggerWatch(). However, DataTree.setWatches() \u2014 the SetWatches/SetWatches2 reconnect replay handler \u2014 still calls watcher.process(event) with null ACL, bypassing the check entirely. It\u0027s important to note that only the path is exposed by this vulnerability, not the data of znode, but since znode path can contain sensitive information like user name or login ID, this issue is potentially critical.\u003cbr\u003e\u003cbr\u003eUsers are recommended to upgrade to version 3.9.6, 3.8.7 which fixes the issue."
}
],
"value": "Information disclosure via SetWatches reconnect replay in Apache ZooKeeper due to missing ACL check.\u00a0An attacker can discover ACL-restricted paths by registering exists-watches on non-existent paths, then reconnecting after the paths are created with restricted ACLs. Issue is caused by incomplete fix for\u00a0CVE-2024-23944 (ZOOKEEPER-4799).\u00a0The fix added ACL checking to WatchManager.triggerWatch(). However, DataTree.setWatches() \u2014 the SetWatches/SetWatches2 reconnect replay handler \u2014 still calls watcher.process(event) with null ACL, bypassing the check entirely. It\u0027s important to note that only the path is exposed by this vulnerability, not the data of znode, but since znode path can contain sensitive information like user name or login ID, this issue is potentially critical.\n\nUsers are recommended to upgrade to version 3.9.6, 3.8.7 which fixes the issue."
}
],
"metrics": [
{
"other": {
"content": {
"text": "critical"
},
"type": "Textual description of severity"
},
"scenarios": [
{
"lang": "en",
"value": "GENERAL"
}
]
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-862",
"description": "CWE-862 Missing Authorization",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-09-16T09:26:37.690Z",
"orgId": "f0158376-9dc2-43b6-827c-5f631a4d8d09",
"shortName": "apache"
},
"references": [
{
"tags": [
"vendor-advisory"
],
"url": "https://lists.apache.org/thread/v0lrwsbdxvx6w67p3z7fxf3hzyncq55l"
}
],
"source": {
"discovery": "UNKNOWN"
},
"title": "Apache ZooKeeper: Information disclosure via SetWatches reconnect replay",
"x_generator": {
"engine": "Vulnogram 0.2.0"
}
}
},
"cveMetadata": {
"assignerOrgId": "f0158376-9dc2-43b6-827c-5f631a4d8d09",
"assignerShortName": "apache",
"cveId": "CVE-2026-59739",
"datePublished": "2026-09-16T09:26:37.690Z",
"dateReserved": "2026-07-06T20:46:19.936Z",
"dateUpdated": "2026-09-16T09:26:37.690Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"vulnerability-lookup:meta": {
"nvd": "{\"cve\":{\"id\":\"CVE-2026-59739\",\"sourceIdentifier\":\"security@apache.org\",\"published\":\"2026-09-16T10:16:51.097\",\"lastModified\":\"2026-09-16T10:16:51.097\",\"vulnStatus\":\"Received\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"Information disclosure via SetWatches reconnect replay in Apache ZooKeeper due to missing ACL check.\u00a0An attacker can discover ACL-restricted paths by registering exists-watches on non-existent paths, then reconnecting after the paths are created with restricted ACLs. Issue is caused by incomplete fix for\u00a0CVE-2024-23944 (ZOOKEEPER-4799).\u00a0The fix added ACL checking to WatchManager.triggerWatch(). However, DataTree.setWatches() \u2014 the SetWatches/SetWatches2 reconnect replay handler \u2014 still calls watcher.process(event) with null ACL, bypassing the check entirely. It\u0027s important to note that only the path is exposed by this vulnerability, not the data of znode, but since znode path can contain sensitive information like user name or login ID, this issue is potentially critical.\\n\\nUsers are recommended to upgrade to version 3.9.6, 3.8.7 which fixes the issue.\"}],\"affected\":[{\"source\":\"security@apache.org\",\"affectedData\":[{\"vendor\":\"Apache Software Foundation\",\"product\":\"Apache ZooKeeper\",\"defaultStatus\":\"unaffected\",\"collectionURL\":\"https://repo.maven.apache.org/maven2\",\"packageName\":\"org.apache.zookeeper:zookeeper\",\"packageURL\":\"pkg:maven/org.apache.zookeeper/zookeeper\",\"versions\":[{\"version\":\"3.9.0\",\"lessThanOrEqual\":\"3.9.5\",\"versionType\":\"maven\",\"status\":\"affected\"},{\"version\":\"3.8.0\",\"lessThanOrEqual\":\"3.8.6\",\"versionType\":\"semver\",\"status\":\"affected\"}]}]}],\"metrics\":{},\"weaknesses\":[{\"source\":\"security@apache.org\",\"type\":\"Primary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-862\"}]}],\"references\":[{\"url\":\"https://lists.apache.org/thread/v0lrwsbdxvx6w67p3z7fxf3hzyncq55l\",\"source\":\"security@apache.org\"}]}}"
}
}
Loading…
Loading…
Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
Loading…
The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
Loading…
Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.
Loading…