GNU libmicrohttpd up to 0.9.75 Multipart Form Parser MHD_create_post_processor boundary out-of-bounds

Summaryinfo

A vulnerability classified as problematic was found in GNU libmicrohttpd up to 0.9.75. Affected is the function MHD_create_post_processor of the component Multipart Form Parser. The manipulation of the argument boundary results in out-of-bounds. This vulnerability is reported as CVE-2023-27371. The attack can be launched remotely. No exploit exists. Upgrading the affected component is advised.

Detailsinfo

A vulnerability classified as problematic has been found in GNU libmicrohttpd up to 0.9.75 (Web Server). Affected is the function MHD_create_post_processor of the component Multipart Form Parser. The manipulation of the argument boundary with an unknown input leads to a out-of-bounds vulnerability. CWE is classifying the issue as CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. This is going to have an impact on availability. CVE summarizes:

GNU libmicrohttpd before 0.9.76 allows remote DoS (Denial of Service) due to improper parsing of a multipart/form-data boundary in the postprocessor.c MHD_create_post_processor() method. This allows an attacker to remotely send a malicious HTTP POST packet that includes one or more '\0' bytes in a multipart/form-data boundary field, which - assuming a specific heap layout - will result in an out-of-bounds read and a crash in the find_boundary() function.

The weakness was disclosed 03/01/2023. The advisory is shared for download at git.gnunet.org. This vulnerability is traded as CVE-2023-27371 since 02/28/2023. There are known technical details, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 237994 (NewStart CGSL MAIN 7.02 : libmicrohttpd Vulnerability (NS-SA-2025-0091)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 0.9.76 eliminates this vulnerability. Applying a patch is able to eliminate this problem. The bugfix is ready for download at git.gnunet.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (237994) and EUVD (EUVD-2023-31147). Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

• Web Server

Vendor

• GNU

Name

• libmicrohttpd

Version

• 0.9.0
• 0.9.1
• 0.9.2
• 0.9.3
• 0.9.4
• 0.9.5
• 0.9.6
• 0.9.7
• 0.9.8
• 0.9.9
• 0.9.10
• 0.9.11
• 0.9.12
• 0.9.13
• 0.9.14
• 0.9.15
• 0.9.16
• 0.9.17
• 0.9.18
• 0.9.19
• 0.9.20
• 0.9.21
• 0.9.22
• 0.9.23
• 0.9.24
• 0.9.25
• 0.9.26
• 0.9.27
• 0.9.28
• 0.9.29
• 0.9.30
• 0.9.31
• 0.9.32
• 0.9.33
• 0.9.34
• 0.9.35
• 0.9.36
• 0.9.37
• 0.9.38
• 0.9.39
• 0.9.40
• 0.9.41
• 0.9.42
• 0.9.43
• 0.9.44
• 0.9.45
• 0.9.46
• 0.9.47
• 0.9.48
• 0.9.49
• 0.9.50
• 0.9.51
• 0.9.52
• 0.9.53
• 0.9.54
• 0.9.55
• 0.9.56
• 0.9.57
• 0.9.58
• 0.9.59
• 0.9.60
• 0.9.61
• 0.9.62
• 0.9.63
• 0.9.64
• 0.9.65
• 0.9.66
• 0.9.67
• 0.9.68
• 0.9.69
• 0.9.70
• 0.9.71
• 0.9.72
• 0.9.73
• 0.9.74
• 0.9.75

License

• open-source

Website

• Vendor: https://www.gnu.org/

CPE 2.3info

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Once again VulDB remains the best source for vulnerability data.

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