CVE-2017-5637
HighPublic exploitUncontrolled Resource Consumption in Apache ZooKeeper
Published May 13, 2022 · Updated Aug 4, 2026 · Also known as DEBIAN-CVE-2017-5637, DLA-986-1, DSA-3871-1, GHSA-7cwj-j333-x7f7, SUSE-SU-2020:1066-1, UBUNTU-CVE-2017-5637
Key Facts
Patch immediately- CVE-2017-5637 is a high-severity vulnerability (CVSS 7.5 v3.1) affecting Zookeeper (Apache), Debian Linux, org.apache.zookeeper:zookeeper (maven) and 22 more products.
- It is not listed in any known-exploited vulnerabilities catalog. Public exploit code is available.
- EPSS estimates a 73% probability of exploitation in the next 30 days.
- Fixed versions are available, including ardana-ansible 8.0+git.1583432621.24fa60e-3.70.1, ardana-barbican 8.0+git.1585152761.8ef3d61-4.33.1, ardana-db 8.0+git.1583944923.03cca6c-3.31.1.
- Brandefense priority: patch immediately, because it is very likely to be exploited soon.
CVSS v3.1
7.5
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS (30-day exploit likelihood)
73%
Higher than 99.4% of all scored CVEs
Exploited in the wild
No known
Not in a known-exploited catalog
Public exploit code
Available
Proof-of-concept or weaponized module
Get the full CVE-2017-5637 brief as a PDF
Every affected product and fixed release, exploitation status and a first 24 hours response checklist, emailed within minutes.
Description
Two four letter word commands "wchp/wchc" are CPU intensive and could cause spike of CPU utilization on Apache ZooKeeper server if abused, which leads to the server unable to serve legitimate client requests. Apache ZooKeeper thru version 3.4.9 and 3.5.2 suffer from this issue, fixed in 3.4.10, 3.5.3, and later.
Affected Products
331 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| ZookeeperApache | 3.4.0, 3.4.1, 3.4.2, 3.4.3, 3.4.4, 3.4.5, 3.4.6, 3.4.7 | 3.4.9-3 |
| Debian LinuxDebian | 8.0 | n/a |
| org.apache.zookeeper:zookeepermaven | >= 3.4.0 | 3.5.3 |
| ardana-ansiblesuse | See advisory | 8.0+git.1583432621.24fa60e-3.70.1 |
| ardana-barbicansuse | See advisory | 8.0+git.1585152761.8ef3d61-4.33.1 |
Patched Releases
ardana-ansible
8.0+git.1583432621.24fa60e-3.70.1
ardana-barbican
8.0+git.1585152761.8ef3d61-4.33.1
ardana-db
8.0+git.1583944923.03cca6c-3.31.1
ardana-monasca
8.0+git.1583944894.38f023a-3.24.1
ardana-mq
8.0+git.1583944811.dc14403-3.19.1
ardana-neutron
8.0+git.1584715262.e4ea620-3.39.1
ardana-octavia
8.0+git.1585171918.418f5cf-3.26.1
ardana-tempest
8.0+git.1585311051.6ab5488-3.33.1
crowbar-core
5.0+git.1585575551.16781d00d-3.38.1
crowbar-core-branding-upstream
5.0+git.1585575551.16781d00d-3.38.1
crowbar-ha
5.0+git.1585316176.344190f-3.32.1
crowbar-openstack
5.0+git.1585304226.2164b7895-4.37.1
documentation-hpe-helion-openstack-installation
8.20200319-1.23.1
documentation-hpe-helion-openstack-operations
8.20200319-1.23.1
documentation-hpe-helion-openstack-opsconsole
8.20200319-1.23.1
documentation-hpe-helion-openstack-planning
8.20200319-1.23.1
documentation-hpe-helion-openstack-security
8.20200319-1.23.1
documentation-hpe-helion-openstack-user
8.20200319-1.23.1
documentation-suse-openstack-cloud-deployment
8.20200319-1.23.1
documentation-suse-openstack-cloud-installation
8.20200319-1.23.1
documentation-suse-openstack-cloud-operations
8.20200319-1.23.1
documentation-suse-openstack-cloud-opsconsole
8.20200319-1.23.1
documentation-suse-openstack-cloud-planning
8.20200319-1.23.1
documentation-suse-openstack-cloud-security
8.20200319-1.23.1
documentation-suse-openstack-cloud-supplement
8.20200319-1.23.1
Timeline
Publicly disclosed
May 13, 2022
Last updated
Aug 4, 2026
Weakness Type
- CWE-20 Improper Input Validation
- CWE-306 Missing Authentication for Critical Function
- CWE-400 Uncontrolled Resource Consumption
References
- advisoryhttps://bugzilla.suse.com/1040519
- advisoryhttps://bugzilla.suse.com/1048688
- advisoryhttps://bugzilla.suse.com/1077718
- advisoryhttps://bugzilla.suse.com/1111180
- advisoryhttps://bugzilla.suse.com/1114157
FAQ
Common Questions.
Two four letter word commands "wchp/wchc" are CPU intensive and could cause spike of CPU utilization on Apache ZooKeeper server if abused, which leads to the server unable to serve legitimate client requests.
Affected: Zookeeper (Apache) versions 3.4.0, 3.4.1, 3.4.2, 3.4.3, 3.4.4, 3.4.5, 3.4.6, 3.4.7; Debian Linux versions 8.0; org.apache.zookeeper:zookeeper (maven) versions >= 3.4.0, among others. The full list is in the CVE brief.
It is not listed in any known-exploited vulnerabilities catalog.
No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.
Public exploit code is available.
Fixed versions are available, including ardana-ansible 8.0+git.1583432621.24fa60e-3.70.1, ardana-barbican 8.0+git.1585152761.8ef3d61-4.33.1, ardana-db 8.0+git.1583944923.03cca6c-3.31.1.
Brandefense priority: patch immediately, because it is very likely to be exploited soon.
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