CVE-2026-29975
📛 CVE Title
CVE-2026-29975
Description
lwjson 1.8.1 contains an improper input validation vulnerability in the streaming JSON parser (lwjson_stream.c). The end-of-string detection logic incorrectly identifies escaped quote characters by only checking the immediately preceding character rather than counting consecutive backslashes, causing valid JSON strings ending with an escaped backslash (like "\\") to never terminate parsing. A remote attacker can send well-formed JSON to cause applications using lwjson_stream_parse() to hang indefinitely, resulting in denial of service.
Overview
- State
- PUBLISHED
- Assigner (CNA)
- mitre
- CVSS severity
- high
- CVSS score
- 7.5 / 10
- CVSS vector
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H- Effective score
- 7.5 / 10 HIGH source: CNA overview
- CWE(s)
- —
- Reserved
- 2026-03-04
- Published
- 2026-05-08 02:00 UTC
- Last updated
- 2026-05-08 20:07 UTC
- Source
- https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/29xxx/CVE-2026-29975.json
- Linked Threat
- CVE-2026-29975 — CVE-2026-29975
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
- 2026-05-08 16:16:10 UTC
- NVD last modified
- 2026-05-12 14:51:21 UTC
- NVD CVSS v3.1
- 7.5 / 10 HIGH source: 134c704f-9b21-4f2e-91b3-4a467353bcc0
- NVD CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H- Exploitability subscore
- 3.9 / 10
- Impact subscore
- 3.6 / 10
- EPSS score
- 0.0017 (probability of exploitation in next 30 days)
- EPSS percentile
- 37.25% vs all CVEs — higher = more likely to be exploited, as of 2026-05-25
NVD-assigned CWE(s):
CWE-835
(differs from the CNA list above)
NVD / KEV / EPSS data refreshed 2026-05-25 17:15 UTC. Re-run the 🛰 Backfill from NVD button above to refresh.
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-2026-28787 - Assigner
- mitre
- Published
- May 8, 2026, 12:00:00 AM
- Updated
- May 8, 2026, 6:07:25 PM
- EUVD base score (CVSS 3.1)
-
7.5 / 10
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - EUVD-reported EPSS
- 0.1700
- Vendors
- n/a
- Products
-
n/a (n/a)
ENISA description: lwjson 1.8.1 contains an improper input validation vulnerability in the streaming JSON parser (lwjson_stream.c). The end-of-string detection logic incorrectly identifies escaped quote characters by only checking the immediately preceding character rather than counting consecutive backslashes, causing valid JSON strings ending with an escaped backslash (like "\\") to never terminate parsing. A remote attacker can send well-formed JSON to cause applications using lwjson_stream_parse() to hang indefinitely, resulting in denial of service.
Affected products (1)
| Vendor | Product | Versions | Platforms |
|---|---|---|---|
| n/a | n/a |
n/a (affected)
|
— |
Vendor references (3)
References embedded in the original CVE record by the assigning CNA.
MITRE references (3) cveawg.mitre.org
Pulled from MITRE's CVE Services API by the 🛰 Backfill from MITRE button.
Web references (3)
DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.
- https://nvd.nist.gov/vuln/detail/CVE-2026-29975 tenable:nvd.nist.gov
- https://www.cve.org/CVERecord?id=CVE-2026-29975 tenable:www.cve.org
- https://www.first.org/epss/ tenable:www.first.org
NVD-tagged references (4)
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://gist.github.com/dwilliams27/b99fd41be5d6848691797042cbfc1103 cve@mitre.org
- https://gist.github.com/dwilliams27/b99fd41be5d6848691797042cbfc1103 134c704f-9b21-4f2e-91b3-4a467353bcc0
- https://github.com/MaJerle/lwjson/blob/develop/lwjson/src/lwjson/lwjson_stream.c#L362-L364 cve@mitre.org
- https://github.com/MaJerle/lwjson/tree/develop cve@mitre.org
Remediations (17)
Remediations are stored against the linked Threat row; the list below is deduplicated across both pages.
-
web:cybersecuritynews.com
Microsoft released an out-of-band hotpatch update on March 13, 2026 , addressing serious security vulnerabilities in Windows 11 versions 24H2 and 25H2.
2026-05-23 21:07 UTC -
web:krebsonsecurity.com
Microsoft Corp. today issued security updates to fix more than 80 vulnerabilities in its Windows operating systems and software. There are no known "zero-day" or actively exploited ...
2026-05-23 21:07 UTC -
web:nvd.nist.gov
This is a potential security issue, you are being redirected to https://nvd.nist.gov
2026-05-23 21:07 UTC -
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.
2026-05-23 21:07 UTC -
web:www.cisa.gov
Updated October 29, 2025: CISA has updated this Alert to include revised information on vulnerable product identification, potential threat activity detections, and additional resources. Microsoft released an update to address a critical remote code execution vulnerability impacting Windows Server Update Service (WSUS) in Windows Server (2012, 2016, 2019, 2022, and 2025), CVE -2025-59287
2026-05-23 21:07 UTC -
web:www.computerworld.com
Each month, the team at Readiness analyzes the latest Patch Tuesday updates from Microsoft and provides detailed, actionable testing guidance. The company's Patch Tuesday release for February ...
2026-05-23 21:07 UTC -
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.
2026-05-23 21:07 UTC -
web:www.techrepublic.com
Microsoft's April 2026 Patch Tuesday fixes 165 vulnerabilities, including two zero-days, in one of the company's largest monthly security updates.
2026-05-23 21:07 UTC -
web:www.windowslatest.com
Windows 11 April 2026 update adds Narrator Copilot support, faster Settings, File Explorer fixes, and key security improvements.
2026-05-23 21:07 UTC -
web:zecurit.com
Get the complete breakdown of Microsoft's May 2026 Patch Tuesday. We analyze the latest security updates and all critical CVEs .
2026-05-23 21:07 UTC -
web:blackswan-cybersecurity.com
Cloud Files API activity originating outside legitimate OneDrive/sync processes. Mitigation Steps: Apply all Windows updates immediately (monitor MSRC for an emergency RedSun-specific patch . None released as of April 17, 2026 ). Supplement Defender with a secondary EDR solution (e.g., Huntress) capable of detecting Defender bypasses.
2026-05-26 02:47 UTC -
web:blog.qualys.com
Microsoft has rolled out its March 2026 Patch Tuesday updates, delivering a fresh batch of security fixes designed to keep Windows environments protected from emerging threats.
2026-05-26 02:47 UTC -
web:cyberpress.org
The U.S. Cybersecurity and Infrastructure Security Agency (CISA) has added two actively exploited Microsoft Defender vulnerabilities to its Known Exploited Vulnerabilities (KEV) catalog, issuing an urgent remediation directive for federal agencies with a due date of June 3, 2026 .
2026-05-26 02:47 UTC -
web:krebsonsecurity.com
October's Patch Tuesday also marks the final month that Microsoft will ship security updates for Windows 10 systems.
2026-05-26 02:47 UTC -
web:thehackernews.com
Microsoft's January 2026 Patch Tuesday fixes 114 Windows flaws, including an actively exploited Desktop Window Manager bug added to CISA's KEV list.
2026-05-26 02:47 UTC -
web:windowsreport.com
Microsoft has released its May 2026 Patch Tuesday updates for Windows 11 and Windows 10, shipping as KB5089549 and KB5087544. The updates include fixes for more than 130 security vulnerabilities across Windows, Office, SharePoint, DNS components, and core system services, as Bleeping Computer writes. While no publicly disclosed zero-day vulnerabilities were reported this month, the […]
2026-05-26 02:47 UTC -
web:www.pcworld.com
This month's Patch Tuesday includes an actively exploited Office zero-day vulnerability and several critical RCE bugs in Windows and Remote Desktop.
2026-05-26 02:47 UTC
AI Forensic Analysis
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Raw JSON
The full cvelistV5 record. Download as CVE-2026-29975.json.
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