CVE-2026-100641

HIGHPre-NVD 8.08.0
EchelonGraph scoreMEDIUM confidence

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

Score 8.0 from GitHub Security Advisory (severity: HIGH) published 2026-09-26. A secondary CVSS source baseline 8.0; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: EPSS, GitHub Security Advisory, a secondary CVSS source
Trending — 3 sources updated this weekElevated

Also known asEUVD-2026-87735 (ENISA EUVD) · GHSA-wvmc-29rv-83j2 (GitHub Security Advisories)Source: ENISA EUVD

8.0EG
EchelonGraph verdictPlan mitigationNo release containing the referenced fix is confirmed: check the referenced fix and the vendor's advisory for a release that contains it; until one is applied, restrict network exposure of the affected system or apply the vendor's mitigation on your normal schedule at low or medium mission impact and sooner than that at high (the SSVC decision on this page).
  • CISA's Vulnrichment rates exploitation as PoC; EchelonGraph holds no exploit-code reference for it
CISA-KEV: Not listedEPSS PROB: 0.7%CVSS: 8.0Exploit: No code on recordExposed services: Not assessed

A fix is referenced (a reference tagged "Patch", often a source commit), but no release containing it is confirmed — find the release that contains it; until it is applied, mitigate (WAF / firewall / segmentation).

SiYuan before v3.8.4 does not HTML-escape stored flashcard block content before interpolating it into the card-manager list markup. Block content returned by /api/riff/getRiffCards is inserted into a card item template in app/src/card/viewCards.ts and assigned to listElement.innerHTML, so content such as becomes an executable event-handler attribute. Because the SiYuan desktop (Electron) main window is created with nodeIntegration enabled and contextIsolation disabled, an administrator who opens the card manager on a workspace containing attacker-supplied flashcard content (for example introduced through contribution or import) executes the attacker's script in a privileged renderer, which can lead to arbitrary code execution on the host. The affected endpoint remains behind authentication and administrator-role checks; this is an untrusted-content-to-privileged-renderer issue, not an authorization bypass.

CVSS v3
8.0
EG Score
8.0HIGHmedium confidence
EG Risk
52
EG Risk 52/100

EG Risk is EchelonGraph's 0–100 priority score. It fuses impact severity (EG Severity, the CVSS base score, never the KEV-floored or EPSS-lifted EG Score) with real-world exploitation and automatability, under weights EchelonGraph set by hand, so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner.

How it’s computed (value × EchelonGraph’s weight)
Severity80% × 45%
Impact severity (EG Severity): CVSS 8.0 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation40% × 40%
EchelonGraph's fixed weight for EG-KEV Tier 3 (Elevated): a constant, not a probability.
Automatability0% × 15%
CISA's SSVC Automatable value: no (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at low, Track* at medium and Attend at high mission impact.
Exploitation public PoC (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 referenced, but no release containing it is confirmed. Check the referenced fix and the vendor's advisory for a release that contains it; until one is applied, restrict network exposure of the affected system or apply the vendor's mitigation on your normal schedule at low or medium mission impact and sooner than that at high.
EPSS PROB
0.7%
EPSS %ILE
52nd
KEV
Not listed

What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)

The EG score (8.0): severity, escalated by confirmed exploitation. This CVE's 8.0 is its impact severity (EG Severity), not escalated.

EG Severity
8.0 HIGHCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
EG Likelihood
0.7% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-25). FIRST's exploitation probability, not an EchelonGraph model.
Confirmed exploitation
None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
EG Priority
SSVC Track* at medium mission impactTrack at low, Track* at medium and Attend at high mission impact.CISA BOD 26-04: 14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.No released fix is confirmed on this page, but CISA's timeline does not wait for a fix's release: it starts when an agency identifies the flaw on an asset and updates the CDM Agency and Federal Dashboard, and the directive counts patching, decommissioning the system or another action as remediation. Until a fixed release is applied, mitigate as this page's verdict says. In the directive's words, “Fix on system upgrade” means that, “unless conditions change”, the vulnerability “should be remediated the next time the vulnerable asset receives a scheduled major upgrade or rebuild”: its timelines are “dynamic as facts change”, and a KEV listing shortens them.Each input and its source, and whom BOD 26-04 binds: the SSVC and BOD 26-04 blocks below.

SSVC (CISA's decision table, applied by EchelonGraph)Track at low, Track* at medium and Attend at high mission impact.

A fix is referenced, but no release containing it is confirmed. Check the referenced fix and the vendor's advisory for a release that contains it; until one is applied, restrict network exposure of the affected system or apply the vendor's mitigation on your normal schedule at low or medium mission impact and sooner than that at high.

Exploitation public PoC (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.

No released fix is confirmed on this page, but CISA's timeline does not wait for a fix's release: it starts when an agency identifies the flaw on an asset and updates the CDM Agency and Federal Dashboard, and the directive counts patching, decommissioning the system or another action as remediation. Until a fixed release is applied, mitigate as this page's verdict says. In the directive's words, “Fix on system upgrade” means that, “unless conditions change”, the vulnerability “should be remediated the next time the vulnerable asset receives a scheduled major upgrade or rebuild”: its timelines are “dynamic as facts change”, and a KEV listing shortens them.

The score's inputs: 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

September 26, 2026

Last Modified

October 5, 2026

Advisory Details (6)

Auto-updated Sep 26, 2026
Fix referenced — no release confirmed yet. Sources: github_commit, github.
Web page

SiYuan before v3.8.4 Stored XSS via Unescaped Flashcard Content | Advisories | VulnCheck

https://www.vulncheck.com/advisories/siyuan-before-3.8.4-stored-xss-via-unescaped-flashcard-content
GitHub commit

commit 8641553a1f07 (siyuan-note/siyuan)

Fix landed in siyuan-note/siyuan commit 8641553a1f07 — awaiting tagged release

https://github.com/siyuan-note/siyuan/commit/8641553a1f07374001902d3ce773285db1292b2d
GitHub commit

commit 41b14025b4ac (siyuan-note/siyuan)

Fix landed in siyuan-note/siyuan commit 41b14025b4ac — awaiting tagged release

https://github.com/siyuan-note/siyuan/commit/41b14025b4ac4a8379d1200580344ca18ad152b7
GitHub commit

commit 48c354e7de13 (siyuan-note/siyuan)

Fix landed in siyuan-note/siyuan commit 48c354e7de13 — awaiting tagged release

https://github.com/siyuan-note/siyuan/commit/48c354e7de130aaada9d7120125bbc768344fd3b
GitHub commit

commit 1ecb1c07de49 (siyuan-note/siyuan)

Fix landed in siyuan-note/siyuan commit 1ecb1c07de49 — awaiting tagged release

https://github.com/siyuan-note/siyuan/commit/1ecb1c07de497ff03b585536fe5579291754d96b
GitHub advisoryMentions a patch (unverified)

Unescaped Flashcard Content Enables Code Execution in the Desktop Card Manager · Advisory · siyuan-note/siyuan · GitHub

https://github.com/siyuan-note/siyuan/security/advisories/GHSA-2mmf-4xwm-55rm

Vendor Advisories for CVE-2026-100641(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 9× in last 7d / 70× 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. 2026-11-01 16:33 UTCEPSS rescoreEPSS 0.7% · 52nd percentile
  2. 2026-10-31 16:31 UTCEPSS rescoreEPSS 0.7% · 52nd percentile
  3. 2026-10-30 16:33 UTCEPSS rescoreEPSS 0.7% · 52nd percentile
  4. 2026-10-29 16:32 UTCEPSS rescoreEPSS 0.7% · 51st percentile
  5. 2026-10-28 16:31 UTCEPSS rescoreEPSS 0.7% · 51st percentile
  6. 2026-10-27 16:31 UTCEPSS rescoreEPSS 0.7% · 51st percentile
  7. 2026-10-26 16:30 UTCEPSS rescoreEPSS 0.7% · 51st percentile
  8. 2026-10-26 15:32 UTCEG score recompute
  9. 2026-10-26 15:32 UTCGHSA enrichmentGHSA-wvmc-29rv-83j2 · GitHub severity HIGH · GitHub CVSS 8.0
  10. 2026-10-25 16:32 UTCEPSS rescoreEPSS 0.7% · 51st percentile
  11. 2026-10-25 15:58 UTCEG score recompute
  12. 2026-10-25 00:35 UTCEG score recompute
  13. 2026-10-25 00:35 UTCGHSA enrichmentGHSA-wvmc-29rv-83j2 · GitHub severity HIGH · GitHub CVSS 8.0
  14. 2026-10-24 16:31 UTCEPSS rescoreEPSS 0.5% · 44th percentile
  15. 2026-10-23 16:31 UTCEPSS rescoreEPSS 0.5% · 44th percentile
  16. 2026-10-22 16:33 UTCEPSS rescoreEPSS 0.5% · 44th percentile
  17. 2026-10-21 16:31 UTCEPSS rescoreEPSS 0.5% · 44th percentile
  18. 2026-10-20 16:31 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  19. 2026-10-19 16:31 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  20. 2026-10-18 16:31 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  21. 2026-10-18 05:11 UTCEG score recompute
  22. 2026-10-17 20:14 UTCEG score recompute
  23. 2026-10-17 20:13 UTCGHSA enrichmentGHSA-wvmc-29rv-83j2 · GitHub severity HIGH · GitHub CVSS 8.0
  24. 2026-10-17 16:33 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  25. 2026-10-16 16:40 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
Show 73 more
  1. 2026-10-15 16:31 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  2. 2026-10-14 16:31 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  3. 2026-10-13 16:33 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  4. 2026-10-12 16:41 UTCEG score recompute
  5. 2026-10-12 16:33 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  6. 2026-10-11 23:13 UTCGHSA enrichmentGHSA-wvmc-29rv-83j2 · GitHub severity HIGH · GitHub CVSS 8.0
  7. 2026-10-11 20:16 UTCEG score recompute
  8. 2026-10-11 18:29 UTCEG score recompute
  9. 2026-10-11 15:02 UTCEG score recompute
  10. 2026-10-11 13:47 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  11. 2026-10-11 10:46 UTCGHSA enrichmentGHSA-wvmc-29rv-83j2 · GitHub severity HIGH · GitHub CVSS 8.0
  12. 2026-10-10 22:16 UTCEG score recompute
  13. 2026-10-10 22:16 UTCGHSA enrichmentGHSA-wvmc-29rv-83j2 · GitHub severity HIGH · GitHub CVSS 8.0
  14. 2026-10-10 19:59 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  15. 2026-10-10 09:43 UTCGHSA enrichmentGHSA-wvmc-29rv-83j2 · GitHub severity HIGH · GitHub CVSS 8.0
  16. 2026-10-09 21:16 UTCEG score recompute
  17. 2026-10-09 21:16 UTCGHSA enrichmentGHSA-wvmc-29rv-83j2 · GitHub severity HIGH · GitHub CVSS 8.0
  18. 2026-10-09 20:06 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  19. 2026-10-09 08:50 UTCGHSA enrichmentGHSA-wvmc-29rv-83j2 · GitHub severity HIGH · GitHub CVSS 8.0
  20. 2026-10-08 20:06 UTCEG score recompute
  21. 2026-10-08 20:06 UTCGHSA enrichmentGHSA-wvmc-29rv-83j2 · GitHub severity HIGH · GitHub CVSS 8.0
  22. 2026-10-08 17:11 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  23. 2026-10-08 06:40 UTCEG score recompute
  24. 2026-10-08 06:40 UTCGHSA enrichmentGHSA-wvmc-29rv-83j2 · GitHub severity HIGH · GitHub CVSS 8.0
  25. 2026-10-07 23:47 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  26. 2026-10-07 18:14 UTCGHSA enrichmentGHSA-wvmc-29rv-83j2 · GitHub severity HIGH · GitHub CVSS 8.0
  27. 2026-10-07 05:48 UTCGHSA enrichmentGHSA-wvmc-29rv-83j2 · GitHub severity HIGH · GitHub CVSS 8.0
  28. 2026-10-06 17:21 UTCEG score recompute
  29. 2026-10-06 17:21 UTCGHSA enrichmentGHSA-wvmc-29rv-83j2 · GitHub severity HIGH · GitHub CVSS 8.0
  30. 2026-10-06 15:17 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  31. 2026-10-06 04:55 UTCEG score recompute
  32. 2026-10-06 04:55 UTCGHSA enrichmentGHSA-wvmc-29rv-83j2 · GitHub severity HIGH · GitHub CVSS 8.0
  33. 2026-10-05 17:42 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  34. 2026-10-05 16:28 UTCEG score recompute
  35. 2026-10-05 16:28 UTCGHSA enrichmentGHSA-wvmc-29rv-83j2 · GitHub severity HIGH · GitHub CVSS 8.0
  36. 2026-10-05 16:11 UTCEG score recompute
  37. 2026-10-05 16:11 UTCGHSA enrichmentGHSA-wvmc-29rv-83j2 · GitHub severity HIGH · GitHub CVSS 8.0
  38. 2026-10-05 11:15 UTCEG score recompute
  39. 2026-10-05 11:15 UTCGHSA enrichmentGHSA-wvmc-29rv-83j2 · GitHub severity HIGH · GitHub CVSS 8.0
  40. 2026-10-04 23:21 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  41. 2026-10-04 22:48 UTCGHSA enrichmentGHSA-wvmc-29rv-83j2 · GitHub severity HIGH · GitHub CVSS 8.0
  42. 2026-10-04 10:22 UTCGHSA enrichmentGHSA-wvmc-29rv-83j2 · GitHub severity HIGH · GitHub CVSS 8.0
  43. 2026-10-03 21:55 UTCEG score recompute
  44. 2026-10-03 21:55 UTCGHSA enrichmentGHSA-wvmc-29rv-83j2 · GitHub severity HIGH · GitHub CVSS 8.0
  45. 2026-10-03 14:25 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  46. 2026-10-03 09:19 UTCGHSA enrichmentGHSA-wvmc-29rv-83j2 · GitHub severity HIGH · GitHub CVSS 8.0
  47. 2026-10-02 20:51 UTCEG score recompute
  48. 2026-10-02 20:51 UTCGHSA enrichmentGHSA-wvmc-29rv-83j2 · GitHub severity HIGH · GitHub CVSS 8.0
  49. 2026-10-02 08:24 UTCGHSA enrichmentGHSA-wvmc-29rv-83j2 · GitHub severity HIGH · GitHub CVSS 8.0
  50. 2026-10-01 19:58 UTCEG score recompute
  51. 2026-10-01 19:58 UTCGHSA enrichmentGHSA-wvmc-29rv-83j2 · GitHub severity HIGH · GitHub CVSS 8.0
  52. 2026-10-01 19:49 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  53. 2026-10-01 07:32 UTCGHSA enrichmentGHSA-wvmc-29rv-83j2 · GitHub severity HIGH · GitHub CVSS 8.0
  54. 2026-09-30 19:06 UTCEG score recompute
  55. 2026-09-30 19:06 UTCGHSA enrichmentGHSA-wvmc-29rv-83j2 · GitHub severity HIGH · GitHub CVSS 8.0
  56. 2026-09-30 15:02 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  57. 2026-09-30 06:40 UTCGHSA enrichmentGHSA-wvmc-29rv-83j2 · GitHub severity HIGH · GitHub CVSS 8.0
  58. 2026-09-29 18:14 UTCEG score recompute
  59. 2026-09-29 18:14 UTCGHSA enrichmentGHSA-wvmc-29rv-83j2 · GitHub severity HIGH · GitHub CVSS 8.0
  60. 2026-09-29 15:20 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  61. 2026-09-29 04:51 UTCEG score recompute
  62. 2026-09-29 04:51 UTCGHSA enrichmentGHSA-wvmc-29rv-83j2 · GitHub severity HIGH · GitHub CVSS 8.0
  63. 2026-09-28 16:25 UTCEG score recompute
  64. 2026-09-28 16:25 UTCGHSA enrichmentGHSA-wvmc-29rv-83j2 · GitHub severity HIGH · GitHub CVSS 8.0
  65. 2026-09-28 13:50 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  66. 2026-09-28 03:58 UTCGHSA enrichmentGHSA-wvmc-29rv-83j2 · GitHub severity HIGH · GitHub CVSS 8.0
  67. 2026-09-27 15:32 UTCEG score recompute
  68. 2026-09-27 15:31 UTCGHSA enrichmentGHSA-wvmc-29rv-83j2 · GitHub severity HIGH · GitHub CVSS 8.0
  69. 2026-09-27 03:02 UTCEG score recompute
  70. 2026-09-27 03:01 UTCGHSA enrichmentGHSA-wvmc-29rv-83j2 · GitHub severity HIGH · GitHub CVSS 8.0
  71. 2026-09-26 14:35 UTCEG score recompute
  72. 2026-09-26 13:39 UTCEG score recomputeFirst assessed: 8.0 HIGH
  73. 2026-09-26 13:30 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-100641?
CVE-2026-100641 is a high-severity vulnerability; its CVE record was published on September 26, 2026. SiYuan before v3.8.4 does not HTML-escape stored flashcard block content before interpolating it into the card-manager list markup. Block content returned by /api/riff/getRiffCards is inserted into a card item template in app/src/card/viewCards.ts and assigned to listElement.innerHTML, so content…
When was CVE-2026-100641 made public?
CVE-2026-100641 was made public on September 10, 2026: that is the date its CVE record's CNA, VulnCheck, gives for when the vulnerability was made public. The CVE record itself was published on September 26, 2026. EchelonGraph's copy of the record carries a last-modified date of October 5, 2026; the record at its source may have been updated since.
Is CVE-2026-100641 actively exploited?
CVE-2026-100641 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.7% probability of exploitation in the next 30 days (52nd percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-100641?
CVE-2026-100641 has a CVSS base score of 8.0 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-100641?
A fix for CVE-2026-100641 is referenced (a reference tagged "Patch", often a source commit), but EchelonGraph has no release containing it on record. Check that reference and the vendor's advisory for a release that contains the fix and update to it; until then, restrict network exposure of the affected system or apply the vendor's mitigation. The vendor advisories EchelonGraph has for CVE-2026-100641 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

Explore the affected products and dependency analysis for CVE-2026-100641

Explore →

Is Your Infrastructure Affected by CVE-2026-100641?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.