Unbounded memory allocation in Eclipse Vert.x PostgreSQL client
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- High
- Attack requirements
- None
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Deferred Red Hat: fix deferred
Attack profile from CVSS 4.0 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-789.
Summary
Eclipse Vert.x versions 4.0.0 through 4.5.34, 5.0.0 through 5.0.12, 5.1.0 through 5.1.9 and 5.2.0 are affected in the io.vertx:vertx-pg-client component. The PostgreSQL message decoder reads the 4-byte message length field without any maximum validation (CWE-789). A malicious, compromised, or man-in-the-middle PostgreSQL server can send an oversized length value, so the client keeps accumulating data into memory without bound and can crash with an out-of-memory error. This happens before authentication completes.
Written with Claude Haiku 5.5 from the sources below · 2026-10-28
Description from the CNA
In Eclipse Vert.x versions [4.0.0, 4.5.34] or [5.0.0,5.0.12] or [5.1.0,5.1.9] or [5.2.0, 5.2.0], the PostgreSQL message decoder reads the 4-byte message length field from the PostgreSQL wire protocol without any maximum validation. A malicious, compromised, or man-in-the-middle PostgreSQL server can send a message header with the length field set to an extremely large value (up to Integer.MAX_VALUE), causing the decoder to accumulate subsequent TCP data into a composite buffer without bound, leading to unbounded memory allocation on the client and an out-of-memory crash. This occurs before authentication completes. The impacted component is io.vertx:vertx-pg-client.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Eclipse Foundation | Eclipse Vert.x | 4.0.0 – 4.5.34; 5.0.0 – 5.0.12; 5.1.0 – 5.1.9; 5.2.0 | — | No fix listed | CNA |
- Eclipse Vert.x VendorEclipse Foundation Affected 4.0.0 – 4.5.34; 5.0.0 – 5.0.12; 5.1.0 – 5.1.9; 5.2.0 Fixed in — No fix listed CNA
CPE configurations NVD · 2
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:eclipse:vert.x:*:*:*:*:*:*:*:* | 4.5.0 to before 4.5.35; 5.0.0 to before 5.1.10 | Vulnerable | Eclipse Foundation |
| cpe:2.3:a:eclipse:vert.x:5.2.0:*:*:*:*:*:*:* | 5.2.0 | Vulnerable | Eclipse Foundation |
- cpe:2.3:a:eclipse:vert.x:*:*:*:*:*:*:*:* Versions 4.5.0 to before 4.5.35; 5.0.0 to before 5.1.10 Vulnerable ·Eclipse Foundation
- cpe:2.3:a:eclipse:vert.x:5.2.0:*:*:*:*:*:*:* Versions 5.2.0 Vulnerable ·Eclipse Foundation
Remediation
The sources list no fixed version for Eclipse Vert.x. Red Hat rates this Moderate and lists the Red Hat build of Quarkus as affected with no fix plan available.
Written with Claude Haiku 5.5 from the sources below · 2026-10-28
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat build of Quarkus | Affected | No fix yet: Fix deferred |
Timeline
- 2026-10-16 Threatist record created from CVE-2026-103223
- 2026-10-16 Affected versions changed · Red Hat
- 2026-10-16 CVSS score added · Red Hat
- 2026-10-21 Alias added: GHSA-h6w8-ffgq-ghpg
- 2026-10-21 CVSS score added · NVD
References
More Eclipse Foundation Vert.x vulnerabilities
- TI-2026-06017 Improper certificate validation in Eclipse Vert.x CVSS 4.0MEDIUM 6.9
- TI-2025-10971 In Eclipse Vert.x versions [4.0.0, 4.5.21] and [5.0.0, 5.0.4], a StaticHandler… CVSS 4.0MEDIUM 6.3
- TI-2019-13165 Path traversal in Eclipse Vert.x CVSS 3.1CRITICAL 9.8
- TI-2018-09003 XML external entity injection in Eclipse Vert.x CVSS 3.0CRITICAL 9.8
- TI-2018-09001 Path traversal in Eclipse Vert.x CVSS 3.0CRITICAL 9.8
- TI-2025-10972 Cross-site scripting in Eclipse Foundation Vert.x CVSS 4.0LOW 2.3
Sources
- CVE-2026-103223 · CVE Program
- CVE-2026-103223 · NVD
- FIRST EPSS
- GHSA-h6w8-ffgq-ghpg · GitHub Advisory Database · CC BY 4.0
- CVE-2026-103223 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences