CVE-2025-59777Network attack vector

Unauthenticated application crash via crafted WebSocket packet

Published Nov 10, 2025 · Updated Nov 10, 2025

NULL pointer dereference in GNU libmicrohttpd 1.0.2 and earlier allows remote attackers to crash host applications via a crafted packet. The affected experimental WebSocket library dereferences a NULL pointer while processing the packet, but public sources do not identify the exact function or malformed field. No authentication or user interaction is required, and successful exploitation interrupts only the embedding application process.

CVSS severity8.7
High
EPSS probability0.43%
Next 30 days · Sep 17, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

NULL pointer dereference in GNU libmicrohttpd 1.0.2 and earlier allows remote attackers to crash host applications via a crafted packet. The affected experimental WebSocket library dereferences a NULL pointer while processing the packet, but public sources do not identify the exact function or malformed field. No authentication or user interaction is required, and successful exploitation interrupts only the embedding application process.

The record

CVE
CVE-2025-59777
Published
Nov 10, 2025
Updated
Nov 10, 2025
Vendor
The GnuPG Project
Product
GNU libmicrohttpd
Classifications
CWE-476, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Nov 10, 2025CVE publishedPublication date reported by the CVE source.
  2. Nov 10, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=after the v1.0.2 tag.)
  2. Affected versionversion=v1.0.2 and earlier (The vulnerability remains in the source code up until commit ff13abc on the master branch of the libmicrohttpd Git repository

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

The GnuPG Project · GNU libmicrohttpdversion=after the v1.0.2 tag.); version=v1.0.2 and earlier (The vulnerability remains in the source code up until commit ff13abc on the master branch of the libmicrohttpd Git repository

Published CVSS scores

7.5JPCERT/CCCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
8.7JPCERT/CCCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-476NULL Pointer Dereference
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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