monkey f37e984 HTTP Request mk_http_parser.c header_cmp out-of-bounds

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.4$0-$5k0.00

Summaryinfo

A vulnerability was found in monkey f37e984. It has been rated as problematic. Affected is the function header_cmp of the file mk_server/mk_http_parser.c of the component HTTP Request Handler. This manipulation causes out-of-bounds. This vulnerability is handled as CVE-2025-63656. The attack can be initiated remotely. There is not any exploit available.

Detailsinfo

A vulnerability classified as problematic was found in monkey f37e984. Affected by this vulnerability is the function header_cmp of the file mk_server/mk_http_parser.c of the component HTTP Request Handler. The manipulation with an unknown input leads to a out-of-bounds vulnerability. The CWE definition for the vulnerability is CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. As an impact it is known to affect availability. The summary by CVE is:

An out-of-bounds read in the header_cmp function (mk_server/mk_http_parser.c) of monkey commit f37e984 allows attackers to cause a Denial of Service (DoS) via sending a crafted HTTP request to the server.

The advisory is shared at github.com. This vulnerability is known as CVE-2025-63656 since 10/27/2025. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Technical details are known, but no exploit is available.

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 vulnerability database at EUVD (EUVD-2025-206524). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.4
VulDB Meta Temp Score: 6.4

VulDB Base Score: 5.3
VulDB Temp Score: 5.3
VulDB Vector: 🔒
VulDB Reliability: 🔍

ADP CISA Base Score: 7.5
ADP CISA Vector: 🔒

CVSSv2info

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

Exploitinginfo

Class: Out-of-bounds
CWE: CWE-125 / CWE-119
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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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

10/27/2025 CVE reserved
01/30/2026 +95 days Advisory disclosed
01/30/2026 +0 days VulDB entry created
02/14/2026 +15 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: 426
Status: Confirmed

CVE: CVE-2025-63656 (🔒)
GCVE (CVE): GCVE-0-2025-63656
GCVE (VulDB): GCVE-100-343441
EUVD: 🔒

Entryinfo

Created: 01/30/2026 07:58
Updated: 02/14/2026 02:59
Changes: 01/30/2026 07:58 (55), 01/30/2026 14:29 (1), 02/14/2026 02:59 (11)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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