Security Resilience

CVE-2023-27484

DoS in Crossplane 1.9.0 – 1.9.2

Published
09 March 2023
Modified
21 November 2024
Patch / advisory
CVSS Score v3.1 6.2
Click a component to see what it means
Raw vectorCVSS:3.1/AV:A/AC:L/PR:H/UI:N/S:C/C:N/I:N/A:H
EPSS Score 0.0068 51th percentile
Risk Priority 43 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2023-27484 is a medium-severity Improper Input Validation (CWE-20) vulnerability in Crossplane Crossplane. Its CVSS base score is 6.2 (Medium).

Operationally, ranked in the top 49% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

crossplane-runtime is a set of go libraries used to build Kubernetes controllers in Crossplane and its related stacks. In affected versions an already highly privileged user able to create or update Compositions can specify an arbitrarily high index in a…

more

patch's `ToFieldPath`, which could lead to excessive memory usage once such Composition is selected for a Composite resource. Compositions allow users to specify patches inserting elements into arrays at an arbitrary index. When a Composition is selected for a Composite Resource, patches are evaluated and if a specified index is greater than the current size of the target slice, Crossplane will grow that slice up to the specified index, which could lead to an excessive amount of memory usage and therefore the Pod being OOM-Killed. The index is already capped to the maximum value for a uint32 (4294967295) when parsed, but that is still an unnecessarily large value. This issue has been addressed in versions 1.11.2, 1.10.3, and 1.9.2. Users are advised to upgrade. Users unable to upgrade can restrict write privileges on Compositions to only admin users as a workaround.

CWE(s)

Related Threats

CVEs Like This One

CVE-2023-27483Same vendor: Crossplane
CVE-2026-67978Shared CWE-20, CWE-400
CVE-2023-45167Shared CWE-20, CWE-400
CVE-2025-21230Shared CWE-20, CWE-400
CVE-2026-33287Shared CWE-20, CWE-400
CVE-2026-33285Shared CWE-20, CWE-400
CVE-2026-50196Shared CWE-20, CWE-400
CVE-2023-42503Shared CWE-20, CWE-400
CVE-2023-38737Shared CWE-20, CWE-400
CVE-2024-32007Shared CWE-20, CWE-400

Affected Assets

crossplane
crossplane
1.9.0 — 1.9.2 · 1.10.0 — 1.10.3 · 1.11.0 — 1.11.2

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-20 CWE-400

Security testing and evaluation at multiple SDLC stages directly detects missing or flawed input validation, with the required remediation process ensuring fixes are applied.

addresses: CWE-20 CWE-400

Spam protection mechanisms perform filtering and detection on inbound/outbound messages, directly compensating for missing or weak input validation of unsolicited content.

addresses: CWE-400

Limiting concurrent sessions directly prevents uncontrolled resource consumption by capping the number of active sessions per user or account.

addresses: CWE-400

Analysis identifies uncontrolled resource consumption indicative of denial-of-service or abuse attempts.

addresses: CWE-400

Contingency plan testing includes resource exhaustion scenarios to verify recovery, making it harder for attackers to sustain exploits that cause uncontrolled consumption.

addresses: CWE-400

Updated contingency plans include current procedures to detect, contain, and recover from resource exhaustion, limiting an attacker's ability to sustain impact from uncontrolled consumption.

addresses: CWE-400

Alternate site allows resumption of operations if resource exhaustion at the primary site is exploited to cause unavailability.

addresses: CWE-400

Alternate telecommunications services enable resumption of essential functions when primary services become unavailable due to uncontrolled resource consumption.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

finds

Pre-agreed severity-based prioritization and resource allocation during incident triage reduce the likelihood that an attacker-induced resource exhaustion will overwhelm the organization before corrective action is taken.

finds

Early notification of anomalous resource consumption or system malfunctions enables throttling or isolation before availability is lost.

A.8.15 Logging partial match
finds

Specifying log storage limits and rotation procedures reduces the risk that unbounded log growth will exhaust disk or memory resources and cause denial of service.

finds

Resource-utilization monitoring and alerting on bottlenecks or overloads limits the impact of denial-of-service or resource-exhaustion attacks.

blocks

A.8.20 implements network-level protections (firewalls, segmentation, protocol hardening, monitoring, authentication of systems/devices) that can limit abuse of a resource-consuming weakness but do not stop the weakness from being exploitable; the flaw remains present in the product and can still be triggered from an authorized or internal context.

blocks

Monitoring network service usage and applying controls to restrict access when necessary limits an attacker’s ability to consume excessive resources through unrestricted or unauthenticated service calls.

Hardening callouts derived

DISA STIG baselines are authored against specific weaknesses. Where this CVE cites a broad weakness class, the mapping is not asserted at that abstraction (owner ruling, 2026-09-25: grade only at Base and below), so no rule is shown here rather than a rule shown against the wrong grain.

  • No fine-grained STIG row for CWE-20, a class-level weakness, and none of its children carries one either.
  • No fine-grained STIG row for CWE-400, a class-level weakness. Rules are authored against its narrower children: CWE-770.

References