GHSA-vq76-rxx3-4r4r CVE-2017-17051 PYSEC-2026-692
OpenStack Nova DoS by rebuilding the same instance with a new image multiple times
- Severity
- 8.6 / 10
- High · CVSS 3.0
- Exploit chance (EPSS)
- 1.99%
- Chance of exploitation in the next 30 days. Higher than 80.64% of scored vulnerabilities.
- Known exploited
- No
- Not in CISA's catalog
- Weakness
- CWE-400 Uncontrolled Resource Consumption
- Fix
16.0.4- Upgrade nova to this version or later
Description
An issue was discovered in the default FilterScheduler in OpenStack Nova 16.0.3. By repeatedly rebuilding an instance with new images, an authenticated user may consume untracked resources on a hypervisor host leading to a denial of service, aka doubled resource allocations. This regression was introduced with the fix for OSSA-2017-005 (CVE-2017-16239); however, only Nova stable/pike or later deployments with that fix applied and relying on the default FilterScheduler are affected.
Affected versions
PyPI
| Package | Vulnerable | Fixed in |
|---|---|---|
| nova | < 16.0.4 |
16.0.4 |
How to fix
Move to the fixed version or later with your package manager, update the lockfile, and run your tests. If the package only arrives through another dependency, upgrade that dependency first. If none of its releases pulls a fixed version yet, force the version with your package manager's override.
nova PyPI → 16.0.4
- pip
pip install --upgrade "nova>=16.0.4"- poetry
poetry add "nova>=16.0.4"- uv
uv add "nova>=16.0.4"
Severity breakdown
CVSS 3.0 8.6
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Changed
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Weakness
CWE-400: Uncontrolled Resource Consumption
The product does not properly control the allocation and maintenance of a limited resource.
How to prevent it
- Architecture and Design: Design throttling mechanisms into the system architecture. The best protection is to limit the amount of resources that an unauthorized user can cause to be expended. A strong authentication and access control model will help prevent such attacks from occurring in the first place. The login application should be protected against DoS attacks as much as possible. Limiting the database access, perhaps by caching result sets, can help minimize the resources expended. To further limit the potential for a DoS attack, consider tracking the rate of requests received from users and blocking requests that exceed a defined rate threshold.
- Architecture and Design: Mitigation of resource exhaustion attacks requires that the target system either: recognizes the attack and denies that user further access for a given amount of time, or uniformly throttles all requests in order to make it more difficult to consume resources more quickly than they can again be freed. The first of these solutions is an issue in itself though, since it may allow attackers to prevent the use of the system by a particular valid user. If the attacker impersonates the valid user, they may be able to prevent the user from accessing the server in question. The second solution is simply difficult to effectively institute -- and even when properly done, it does not provide a full solution. It simply makes the attack require more resources on the part of the attacker.
- Architecture and Design: Ensure that protocols have specific limits of scale placed on them.
- Implementation: Ensure that all failures in resource allocation place the system into a safe posture.
References
Advisories
Packages
Other links
- github.com/openstack/nova/commit/25a1d78e83065c5bea5d8e0a017fd9d0914d41d9
- github.com/openstack/nova/commit/fed660c1189fdf4159d97badfdc8c5b35ad14f23
- launchpad.net/bugs/1732976
- review.openstack.org/521662
- review.openstack.org/523214
- security.openstack.org/ossa/OSSA-2017-006.html
- securityfocus.com/bid/102102
Timeline
- Published
- Last updated by the source
- Latest EPSS score
Related advisories
| Advisory | Severity | Why it's related |
|---|---|---|
| GHSA-mfg3-p6m3-gjgr OpenStack Nova: Nova scheduler hint injection bypasses Placement resource claims and scheduling constraints | High | Also affects nova |
| GHSA-m4f3-qp2w-gwh6 OpenStack Nova calls qemu-img without format restrictions for resize | High | Also affects nova |
| GHSA-rm86-h44c-2r2m OpenStack Nova vulnerable to unauthorized access to potentially sensitive data | Medium | Also affects nova |
| GHSA-r4v4-w9pv-6fph OpenStack Cinder, Glance, and Nova vulnerable to arbitrary file access | Medium | Also affects nova |
| GHSA-7h75-hwxx-qpgc OpenStack Cinder, glance, and Nova vulnerable to Path Traversal | Medium | Also affects nova |
| GHSA-v725-c588-h936 OpenStack Nova Changing vnic_type breaks compute service restart | Low | Also affects nova |
| GHSA-22jm-4hxw-35jf OpenStack Nova can leak consoleauth token into log files | Low | Also affects nova |
| GHSA-43cm-73px-5v4m OpenStack Compute (Nova) Resource limit circumvention in Nova private flavors | Low | Also affects nova |
MergeHarbor checks every repository's dependencies against this database, ranks what matters by exploitability and reachability, routes it to the owning team and opens the fix pull request.
Check your repos with MergeHarbor