How severe is CVE-2023-27371?

CVE-2023-27371 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2023-27371 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (66th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-27371?

CVE-2023-27371 affects Gnu Libmicrohttpd. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-27371?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2023-27371 published?

CVE-2023-27371 was published on 2023-02-28 and last updated on 2026-06-17.

CVE-2023-27371

CVE-2023-27371 is a medium-severity vulnerability in Gnu Libmicrohttpd with a CVSS 3.x base score of 5.9. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-125.

Key facts

Severity: Medium (CVSS 3.x base score 5.9)
EPSS exploit prediction: 1% (66th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-125
Affected product: Gnu Libmicrohttpd
Published: 2023-02-28
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is CVE-2023-27371?: 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.
How severe is CVE-2023-27371?: CVE-2023-27371 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2023-27371 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (66th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-27371?: CVE-2023-27371 affects Gnu Libmicrohttpd. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-27371?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2023-27371 published?: CVE-2023-27371 was published on 2023-02-28 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:gnu:libmicrohttpd:*:*:*:*:*:*:*:*

More vulnerabilities in Gnu Libmicrohttpd

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