CVE-2026-46713

Description

Misskey is an open source, federated social media platform. Versions 12.37.0 and later, but prior to 2026.5.4, contain a vulnerability in the JSON-LD signature validation and compaction process that allows spoofed activities to be accepted as valid. This issue has been fixed in version 2026.5.4.

Overview

State: PUBLISHED
Assigner (CNA): GitHub_M
CVSS severity: CRITICAL
CVSS score: 9.2 / 10
CVSS vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:H/VA:N/SC:N/SI:H/SA:N
Effective score: 9.2 / 10 CRITICAL source: CNA overview
CWE(s): CWE-347
Reserved: 2026-05-15
Published: 2026-08-03 21:37 UTC
Last updated: 2026-08-03 21:44 UTC
Source: https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/46xxx/CVE-2026-46713.json
Linked Threat: CVE-2026-46713 — Misskey: JSON-LD signature validation + compaction may lead to improper activity handling

NVD triage scoring NVD CVE 2.0

Layer NVD adds on top of the CNA's CVE record — published / last-modified timestamps, exploitability / impact subscores, and the FIRST.org EPSS probability that this CVE will be exploited in the wild in the next 30 days.

NVD published: 2026-08-03 22:16:49 UTC
NVD last modified: 2026-08-04 17:16:54 UTC
EPSS score: 0.0017 (probability of exploitation in next 30 days)
EPSS percentile: 7.08% vs all CVEs — higher = more likely to be exploited, as of 2026-08-04

European Union Vulnerability Database ENISA EUVD

ENISA's official EU repository for curated vulnerability intelligence. Carries a separate identifier (EUVD-YYYY-NNNN) and frequently exposes an earlier-published description + CVSS than NVD does.

EUVD ID: EUVD-2026-52485
Assigner: GitHub_M
Published: Aug 3, 2026, 9:37:45 PM
Updated: Aug 4, 2026, 3:44:53 PM
EUVD base score (CVSS 4.0): 9.2 / 10
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:H/VA:N/SC:N/SI:H/SA:N
EUVD-reported EPSS: 0.0000
Vendors: misskey-dev
Products: misskey (12.37.0, < 2026.5.4)

ENISA description: Misskey is an open source, federated social media platform. Versions 12.37.0 and later, but prior to 2026.5.4, contain a vulnerability in the JSON-LD signature validation and compaction process that allows spoofed activities to be accepted as valid. This issue has been fixed in version 2026.5.4.

EUVD references (2)

Affected products (1)

Vendor	Product	Versions	Platforms
misskey-dev	misskey	`>= 12.37.0, < 2026.5.4` (affected)	—

Vendor references (2)

References embedded in the original CVE record by the assigning CNA.

https://github.com/misskey-dev/misskey/security/advisories/GHSA-w8x2-gpq6-jxvf x_refsource_CONFIRM
https://github.com/misskey-dev/misskey/releases/tag/2026.5.4 x_refsource_MISC

Web references (0)

DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.

No web references attached yet.

NVD-tagged references (2)

Reference list NVD curates from the CNA record, vendor advisories, and third-party reports. The tag chips below are NVD's analyst-assigned categories.

https://github.com/misskey-dev/misskey/releases/tag/2026.5.4 security-advisories@github.com
https://github.com/misskey-dev/misskey/security/advisories/GHSA-w8x2-gpq6-jxvf security-advisories@github.com

Remediations (10)

Remediations are stored against the linked Threat row; the list below is deduplicated across both pages.

RHSB-2026-008 Traffic Control Privilege Escalation - Linux Kernel (CVE ...

web:access.redhat.com

Executive Summary An Important privilege escalation flaw ( CVE - 2026 -46331) was found in the Linux kernel's traffic control subsystem (act_pedit). A missing bounds check allows an out-of-bounds write, enabling corruption of page cache memory. A user with a local account could exploit this flaw to gain system administrator (root) access. Affected Products The following Red Hat product versions ...

2026-08-04 20:25 UTC
April 2026 Critical Patch Update Released | security - Oracle Blogs

web:blogs.oracle.com

For more information about the Critical Patch Update program, see the security vulnerability remediation practices page located on the Oracle Trust Center.

2026-08-04 20:25 UTC
May 2026 Critical Security Patch Update Released - Oracle Blogs

web:blogs.oracle.com

For more information about the Critical Security Patch Update program, see the security vulnerability remediation practices page located on the Oracle Trust Center.

2026-08-04 20:25 UTC
Nvd - Cve-2024-46713

web:nvd.nist.gov

Description In the Linux kernel, the following vulnerability has been resolved: perf/aux: Fix AUX buffer serialization Ole reported that event->mmap_mutex is strictly insufficient to serialize the AUX buffer, add a per RB mutex to fully serialize it. Note that in the lock order comment the perf_event::mmap_mutex order was already wrong, that is, it nesting under mmap_lock is not new with this ...

2026-08-04 20:25 UTC
Security Update Guide - Microsoft

web:portal.msrc.microsoft.com

The Security Update Guide provides information on the latest Microsoft security updates, helping users understand and address potential vulnerabilities effectively.

2026-08-04 20:25 UTC
SAP Security Patch Day - June 2026

web:support.sap.com

SAP security Patch Day Bulletin This post shares the information on security notes that remediate vulnerabilities discovered in SAP products. SAP strongly recommends that the customer visits the support portal and applies patches on priority to protect their SAP landscape. On 9th of June 2026 , SAP security patch day saw the release of 15 new security notes.

2026-08-04 20:25 UTC
Addressing Exchange Server May 2026 vulnerability CVE-2026-42897 ...

web:techcommunity.microsoft.com

Hi team, Our organization has successfully implemented the recommended mitigation for CVE - 2026 -42897. However, we are currently experiencing the documented known issues within our environment. Could the Exchange team kindly provide a tentative timeline or ETA for a permanent security update that resolves the underlying vulnerability while addressing these known issues? We would greatly ...

2026-08-04 20:25 UTC
Patch Smarter, Not Harder - CISA

web:www.cisa.gov

The median time for full resolution rose to 43 days. Defenders need greater clarity and speed to patch systems in today's threat landscape. We must flip the script on patching prioritization: patch smarter, not harder.

2026-08-04 20:25 UTC
Oracle Critical Patch Update Advisory - April 2026

web:www.oracle.com

This Critical Patch Update contains 481 new security patches across the product families listed below. Please note that an MOS note summarizing the content of this Critical Patch Update and other Oracle Software Security Assurance activities is located at April 2026 Critical Patch Update: Executive Summary and Analysis.

2026-08-04 20:25 UTC
Oracle Critical Security Patch Update Advisory - June 2026

web:www.oracle.com

Additional CVEs addressed are: The patch for CVE - 2026 -34481 also addresses CVE - 2026 -34477, CVE - 2026 -34478, CVE - 2026 -34479, and CVE - 2026 -34480. Oracle Fusion Middleware Risk Matrix This Critical Security Patch Update contains 106 new security patches for Oracle Fusion Middleware. 53 of these vulnerabilities may be remotely exploitable without authentication, i.e., may be exploited over a ...

2026-08-04 20:25 UTC

AI Forensic Analysis

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Raw JSON

The full cvelistV5 record. Download as CVE-2026-46713.json.

{
  "containers": {
    "cna": {
      "affected": [
        {
          "product": "misskey",
          "vendor": "misskey-dev",
          "versions": [
            {
              "status": "affected",
              "version": ">= 12.37.0, < 2026.5.4"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Misskey is an open source, federated social media platform. Versions 12.37.0 and later, but prior to 2026.5.4, contain a vulnerability in the JSON-LD signature validation and compaction process that allows spoofed activities to be accepted as valid. This issue has been fixed in version 2026.5.4."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "NETWORK",
            "baseScore": 9.2,
            "baseSeverity": "CRITICAL",
            "privilegesRequired": "NONE",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "HIGH",
            "userInteraction": "NONE",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:H/VA:N/SC:N/SI:H/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "NONE",
            "vulnConfidentialityImpact": "LOW",
            "vulnIntegrityImpact": "HIGH"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-347",
              "description": "CWE-347: Improper Verification of Cryptographic Signature",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-03T21:44:56.164Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/misskey-dev/misskey/security/advisories/GHSA-w8x2-gpq6-jxvf",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/misskey-dev/misskey/security/advisories/GHSA-w8x2-gpq6-jxvf"
        },
        {
          "name": "https://github.com/misskey-dev/misskey/releases/tag/2026.5.4",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/misskey-dev/misskey/releases/tag/2026.5.4"
        }
      ],
      "source": {
        "advisory": "GHSA-w8x2-gpq6-jxvf",
        "discovery": "UNKNOWN"
      },
      "title": "Misskey: JSON-LD signature validation + compaction may lead to improper activity handling"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-46713",
    "datePublished": "2026-08-03T21:37:45.657Z",
    "dateReserved": "2026-05-15T23:26:58.309Z",
    "dateUpdated": "2026-08-03T21:44:56.164Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}