CVE-2018-12537

Moderate severity vulnerability that affects io.vertx:vertx-core

5.3 MediumPublic exploitFix available

In Eclipse Vert.x version 3.0 to 3.5.1, the HttpServer response headers and HttpClient request headers do not filter carriage return and line feed characters from the header value. This allow unfiltered values to inject a new header in the client request or server response.

Attack profile

How easy it is to exploit

Attack vector: Network
Complexity: Low
Privileges needed: None
User interaction: None

What an attacker can affect

Confidentiality: None
Integrity: Low
Availability: None

Exploit likelihood

2.48%Down 4.6 points since Apr 14, 2021

What each source reports

NVD Score used 5.3

Record: CVE-2018-12537
CVSS 3.0: 5.3 MediumCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
CVSS 2.0: 5.0 MediumAV:N/AC:L/Au:N/C:N/I:P/A:N
Weakness: CWE-93, CWE-20
Updated: 2026-11-02

CVE List No score

Record: CVE-2018-12537
Weakness: CWE-93
Updated: 2026-11-02

EUVDEUVD-2018-0516 No score

Record: EUVD-2018-0516
Updated: 2026-11-03

GitHub AdvisoriesGHSA-6cw8-7j6c-hccp No score

Moderate severity vulnerability that affects io.vertx:vertx-core

Record: GHSA-6cw8-7j6c-hccp
Weakness: CWE-93
Updated: 2026-11-02

OSV 5.3

Record: CVE-2018-12537
CVSS 3.0: 5.3 MediumCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
Updated: 2026-11-02

OSVGHSA-6cw8-7j6c-hccp No score

Moderate severity vulnerability that affects io.vertx:vertx-core

Record: GHSA-6cw8-7j6c-hccp
Weakness: CWE-93
Updated: 2026-11-02

Affected products

Affected packages

Affected packages
Package	Affected	Fixed
`io.vertx:vertx-core` Maven	3.0.0 up to 3.5.2	3.5.2
`io.vertx:vertx-core` Maven	3.0.0 up to 3.5.2, plus listed versions 3.0.0-dev_preview13.1.03.2.03.2.13.3.0 Show 15 moreShow less 3.3.0.CR13.3.0.CR23.3.13.3.23.3.33.4.03.4.0.Beta13.4.13.4.23.5.03.5.0.Beta13.5.13.5.2.CR13.5.2.CR23.5.2.CR3	3.5.2

Public exploits

Links only. Every CVE stores no exploit code.

Public exploits
Source	Link	Date
PoC in GitHub	tafamace/CVE-2018-12537	2018-11-19

History

History
Recorded	Changed	Sources
Nov 3, 2026	aliases, products	EUVD
Nov 2, 2026	first indexed	CVE List, GitHub Advisories, NVD, OSV, PoC in GitHub

Dates are when Every CVE recorded each change. Upstream dates may differ.

In short

CVE-2018-12537 is a medium vulnerability (CVSS 5.3) in Eclipse Vert.x, published August 14, 2018. Public exploit code exists. EPSS puts the chance of exploitation in the next 30 days at 2.48%, the 84th percentile. Fixed in io.vertx:vertx-core 3.5.2.