CVE-2026-54525

HIGHPre-NVD 8.88.8
EchelonGraph scoreMEDIUM confidence

“—” beside the score: it is equal to the CVSS score beside it.

This high-severity CVE scores 8.8 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.4% (35th percentile of EPSS-scored CVEs). No GitHub Security Advisory CVSS is on record for this CVE.

Triggered by: Headline CVSS from a secondary CVSS source
Sources: EPSS, a secondary CVSS source
Trending — 3 sources updated this week
8.8EG
EchelonGraph verdictPlan a fixRemediate within your standard update timelines (the SSVC decision on this page).
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0.4%CVSS: 8.8Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

Markdown Preview Enhanced is a Markdown preview extension for Visual Studio Code. Prior to 0.8.28, Markdown Preview Enhanced preview-link handling passes a decoded, Markdown-controlled link target to a Windows file-opening helper that invokes child_process.exec with the start command. When a Windows user opens an untrusted Markdown file and clicks a crafted external or unsupported-scheme link, shell metacharacters in the decoded target are interpreted by cmd.exe as command separators, allowing an attacker-selected command to run with the privileges of the current VS Code user. The attack requires one normal preview-link click but does not require malicious workspace configuration, script execution to be enabled, or additional files. This issue is fixed in version 0.8.28.

CVSS v3
8.8
EG Score
8.8HIGHmedium confidence
EG Risk
40
EG Risk 40/100

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed (value × EchelonGraph’s weight)
Severity88% × 45%
The EG Score, 8.8 of 10.
Exploitation0.4% × 40%
FIRST EPSS: the 30-day exploitation probability when EchelonGraph scored this CVE.
Automatability0% × 15%
CISA's SSVC Automatable value: no (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at low or medium mission impact; Track* at high (mission-essential systems).
Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE.
Action: A fix is available. Apply it within your standard update timelines.
EPSS PROB
0.4%
EPSS %ILE
35th
KEV
Not listed

SSVC (CISA's decision table, applied by EchelonGraph)Track at low or medium mission impact; Track* at high (mission-essential systems).

A fix is available. Apply it within your standard update timelines.

Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table

BOD 26-04 (CISA's remediation timeline, Table 1)14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.

In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it

Published

October 14, 2026

Last Modified

October 16, 2026

Advisory Details (7)

Auto-updated Oct 14, 2026
🔬 Proof of concept available. Patch available. Sources: github_commit, github_pr, github_release, github.
GitHub advisoryMentions a patch (unverified)🟡 PoC Available

One Click RCE via Markdown Link Command Injection on Windows · Advisory · shd101wyy/vscode-markdown-preview-enhanced · GitHub

https://github.com/shd101wyy/vscode-markdown-preview-enhanced/security/advisories/GHSA-7v6f-3vq6-r373
GitHub release Patch Available

0.8.28

Patch available: shd101wyy/vscode-markdown-preview-enhanced 0.8.28

https://github.com/shd101wyy/vscode-markdown-preview-enhanced/releases/tag/0.8.28
GitHub pull request Patch Available

0.8.28

Patch available: shd101wyy/vscode-markdown-preview-enhanced 0.8.28 (PR #2318 merged 2026-06-05)

https://github.com/shd101wyy/vscode-markdown-preview-enhanced/pull/2318
GitHub commit Patch Available

commit dcd80281c986 (shd101wyy/vscode-markdown-preview-enhanced)

Patch available: shd101wyy/vscode-markdown-preview-enhanced 0.8.28 (contains commit dcd80281c986)

https://github.com/shd101wyy/vscode-markdown-preview-enhanced/commit/dcd80281c986293b93d9f1af34ced64dcb230c77
GitHub release Patch Available

0.9.29

Patch available: shd101wyy/crossnote 0.9.29

https://github.com/shd101wyy/crossnote/releases/tag/0.9.29
GitHub pull request Patch Available

0.9.29

Patch available: shd101wyy/crossnote 0.9.29 (PR #442 merged 2026-06-05)

https://github.com/shd101wyy/crossnote/pull/442
GitHub commit Patch Available

commit 5588ca2121c3 (shd101wyy/crossnote)

Patch available: shd101wyy/crossnote 0.9.29 (contains commit 5588ca2121c3)

https://github.com/shd101wyy/crossnote/commit/5588ca2121c3da43fe331575dc5cf4ef347b91ee

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 8× in last 7d / 8× in last 30d)

Each row is a time one of our pipelines fetched, updated or re-scored this CVE. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. An arrow marks a change the record states ("CVSS v3 → 9.1"); EPSS and GHSA rows show the values recorded at that time, not what changed (EPSS values are rounded; hover one for the exact figures). Most recent first.

  1. 2026-10-16 16:42 UTCEPSS rescoreEPSS 0.4% · 35th percentile
  2. 2026-10-16 16:10 UTCEG score recompute
  3. 2026-10-15 16:32 UTCEPSS rescoreEPSS 0.4% · 35th percentile
  4. 2026-10-15 16:30 UTCEG score recompute
  5. 2026-10-15 15:24 UTCEG score recompute
  6. 2026-10-14 19:34 UTCEG score recompute
  7. 2026-10-14 19:10 UTCEG score recomputeFirst assessed: 8.8 HIGH
  8. 2026-10-14 19:09 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-54525?
CVE-2026-54525 is a high-severity vulnerability; its CVE record was published on October 14, 2026. Markdown Preview Enhanced is a Markdown preview extension for Visual Studio Code. Prior to 0.8.28, Markdown Preview Enhanced preview-link handling passes a decoded, Markdown-controlled link target to a Windows file-opening helper that invokes child_process.exec with the start command. When a…
When was the CVE record for CVE-2026-54525 published?
The CVE record for CVE-2026-54525 was published on October 14, 2026. That is the record's publication date; the vulnerability itself may have been made public earlier. EchelonGraph's copy of the record carries a last-modified date of October 16, 2026; the record at its source may have been updated since.
Is CVE-2026-54525 actively exploited?
CVE-2026-54525 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.4% probability of exploitation in the next 30 days (35th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-54525?
CVE-2026-54525 has a CVSS base score of 8.8 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-54525?
A fix for CVE-2026-54525 is available: update to the fixed version the vendor names in its advisory.

Dependency Blast Radius

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