HAProxy mjson Parsing Library denial of service

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.5$0-$5k0.00

Summaryinfo

A vulnerability labeled as problematic has been found in HAProxy. This issue affects some unknown processing of the component mjson Parsing Library. Executing a manipulation can lead to denial of service. This vulnerability is handled as CVE-2025-11230. There is not any exploit available.

Detailsinfo

A vulnerability classified as problematic was found in HAProxy (the affected version unknown). This vulnerability affects an unknown part of the component mjson Parsing Library. The manipulation with an unknown input leads to a denial of service vulnerability. The CWE definition for the vulnerability is CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. As an impact it is known to affect availability. CVE summarizes:

Inefficient algorithm complexity in mjson in HAProxy allows remote attackers to cause a denial of service via specially crafted JSON requests.

The advisory is shared for download at bugzilla.redhat.com. This vulnerability was named CVE-2025-11230. There are neither technical details nor an exploit publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 275803 (AlmaLinux 9 : haproxy (ALSA-2025:21693)), which helps to determine the existence of the flaw in a target environment.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the databases at Tenable (275803), EUVD (EUVD-2025-198149) and CERT Bund (WID-SEC-2025-2209). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Affected

  • Red Hat Enterprise Linux
  • Ubuntu Linux
  • SUSE Linux
  • Oracle Linux
  • RESF Rocky Linux
  • HAProxy HAProxy
  • HAProxy ALOHA

Productinfo

Type

Name

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.5
VulDB Meta Temp Score: 5.5

VulDB Base Score: 3.5
VulDB Temp Score: 3.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 7.5
CNA Vector: 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Denial of service
CWE: CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 275803
Nessus Name: AlmaLinux 9 : haproxy (ALSA-2025:21693)

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

11/18/2025 Advisory disclosed
11/18/2025 +0 days VulDB entry created
01/21/2026 +64 days VulDB entry last update

Sourcesinfo

Advisory: bugzilla.redhat.com
Status: Not defined

CVE: CVE-2025-11230 (🔒)
GCVE (CVE): GCVE-0-2025-11230
GCVE (VulDB): GCVE-100-332776
EUVD: 🔒
CERT Bund: WID-SEC-2025-2209 - HAProxy und HAProxy ALOHA: Schwachstelle ermöglicht Denial of Service

Entryinfo

Created: 11/18/2025 10:10
Updated: 01/21/2026 09:05
Changes: 11/18/2025 10:10 (49), 11/19/2025 11:59 (12), 11/19/2025 13:57 (1), 11/20/2025 04:30 (2), 01/21/2026 09:05 (7)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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