CVE-2026-54570

MEDIUMPre-NVD 6.96.9
EchelonGraph scoreMEDIUM confidence

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

This medium-severity CVE scores 6.9 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.3% (26th 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
Elevated

Also known asEUVD-2026-61128 (ENISA EUVD) · GHSA-pgww-w46g-26qg (GitHub Security Advisories)Source: ENISA EUVD

6.9EG
EchelonGraph verdictPlan a fixRemediate within your standard update timelines (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: 0.3%CVSS: 6.9Exploit: No code on recordExposed services: Not assessed

A fix is available — apply it.

AngleSharp is a .NET library for parsing angle bracket based hyper-texts. Prior to 1.5.0, MathAnnotationXmlElement in AngleSharp/Mathml/Dom/Internal/MathAnnotationXmlElement.cs is not treated as an HTML integration point when its encoding attribute is text/html or application/xhtml+xml, causing Consume in AngleSharp/Html/Parser/HtmlDomBuilder.cs to route tokens through foreign-content parsing instead of HTML parsing. A sanitizer can therefore observe a different DOM from the browser that reparses the serialized output. An attacker can combine this namespace differential with markup-breaking characters in an attribute value so that an element hidden from the sanitizer becomes active script-capable HTML after browser reparse, resulting in mutation cross-site scripting. This issue is fixed in version 1.5.0.

CVSS v3
6.9
EG Score
6.9MEDIUMmedium confidence
EG Risk
47
EG Risk 47/100

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)
Severity69% × 45%
Impact severity (EG Severity): CVSS 6.9 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 or medium mission impact; Track* at high (mission-essential systems).
Exploitation public PoC (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (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
0.3%
EPSS %ILE
26th
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 (6.9): severity, escalated by confirmed exploitation. This CVE's 6.9 is its impact severity (EG Severity), not escalated.

EG Severity
6.9 MEDIUMCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.a secondary CVSS source · CVSS v3.0 or v3.1
EG Likelihood
0.3% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-24). 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 or medium mission impact; Track* at high (mission-essential systems).CISA BOD 26-04: 60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.Each input and its source: the SSVC and BOD 26-04 blocks below.

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 public PoC (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (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)60 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 partial (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

July 17, 2026

Last Modified

September 18, 2026

Advisory Details (3)

Auto-updated Aug 18, 2026
Patch available. Sources: github, github_commit, github_release.
GitHub release Patch Available

1.5.0

Patch available: AngleSharp/AngleSharp 1.5.0

https://github.com/AngleSharp/AngleSharp/releases/tag/1.5.0
GitHub commit Patch Available

commit 8033a5c690af (AngleSharp/AngleSharp)

Patch available: AngleSharp/AngleSharp 1.5.0 (contains commit 8033a5c690af)

https://github.com/AngleSharp/AngleSharp/commit/8033a5c690af9c2c443f58e34875343fa4cc1d07
GitHub advisoryMentions a patch (unverified)

HTML5 Spec Compliance: mXSS via annotation-xml HTML Integration Point Bypass · Advisory · AngleSharp/AngleSharp · GitHub

https://github.com/AngleSharp/AngleSharp/security/advisories/GHSA-pgww-w46g-26qg

Vendor Advisories for CVE-2026-54570(1)

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

Affected Packages

(1 across 1 ecosystem)
NuGet(1)
PackageVulnerable rangeFix by version rangeDependents
AngleSharp0.10.0 ... 1.4.0 (239 versions)
  • every version up to 1.5.0: fixed in 1.5.0
—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 9× in last 7d / 39× 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. 2026-10-27 16:32 UTCEPSS rescoreEPSS 0.3% · 26th percentile
  2. 2026-10-26 16:31 UTCEPSS rescoreEPSS 0.3% · 25th percentile
  3. 2026-10-25 16:33 UTCEPSS rescoreEPSS 0.3% · 25th percentile
  4. 2026-10-25 14:19 UTCEG score recompute
  5. 2026-10-24 16:33 UTCEPSS rescoreEPSS 0.3% · 25th percentile
  6. 2026-10-23 16:32 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  7. 2026-10-22 21:20 UTCEG score recompute
  8. 2026-10-22 16:34 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  9. 2026-10-21 16:33 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  10. 2026-10-20 16:33 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  11. 2026-10-19 16:32 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  12. 2026-10-18 16:32 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  13. 2026-10-18 03:30 UTCEG score recompute
  14. 2026-10-17 16:34 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  15. 2026-10-16 16:42 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  16. 2026-10-15 16:32 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  17. 2026-10-14 16:33 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  18. 2026-10-13 16:34 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  19. 2026-10-12 16:34 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  20. 2026-10-12 15:56 UTCEG score recompute
  21. 2026-10-11 19:39 UTCEG score recompute
  22. 2026-10-11 16:54 UTCEG score recompute
  23. 2026-10-11 14:17 UTCEG score recompute
  24. 2026-10-11 13:49 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  25. 2026-10-10 20:00 UTCEPSS rescoreEPSS 0.3% · 24th percentile
Show 67 more
  1. 2026-10-09 20:07 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  2. 2026-10-08 17:12 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  3. 2026-10-07 23:48 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  4. 2026-10-06 15:18 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  5. 2026-10-05 17:43 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  6. 2026-10-04 23:22 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  7. 2026-10-03 14:26 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  8. 2026-10-02 17:56 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  9. 2026-10-01 19:50 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  10. 2026-10-01 10:26 UTCEG score recompute
  11. 2026-09-30 15:03 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  12. 2026-09-29 15:22 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  13. 2026-09-28 13:51 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  14. 2026-09-28 07:50 UTCEG score recompute
  15. 2026-09-27 13:48 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  16. 2026-09-26 15:59 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  17. 2026-09-24 14:04 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  18. 2026-09-23 02:24 UTCEG score recompute
  19. 2026-09-20 20:16 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  20. 2026-09-18 20:35 UTCEG score recompute
  21. 2026-09-18 19:28 UTCEPSS rescoreEPSS 0.2% · 16th percentile
  22. 2026-09-17 19:31 UTCEPSS rescoreEPSS 0.2% · 16th percentile
  23. 2026-09-17 10:14 UTCEG score recompute
  24. 2026-09-16 14:08 UTCEPSS rescoreEPSS 0.2% · 16th percentile
  25. 2026-09-16 05:15 UTCEPSS rescoreEPSS 0.2% · 16th percentile
  26. 2026-09-15 03:11 UTCEPSS rescoreEPSS 0.2% · 15th percentile
  27. 2026-09-14 06:51 UTCEG score recompute
  28. 2026-09-13 16:47 UTCEPSS rescoreEPSS 0.2% · 15th percentile
  29. 2026-09-13 04:54 UTCEG score recompute
  30. 2026-09-11 21:05 UTCEG score recompute
  31. 2026-09-11 14:53 UTCEPSS rescoreEPSS 0.2% · 15th percentile
  32. 2026-09-10 09:35 UTCEPSS rescoreEPSS 0.2% · 15th percentile
  33. 2026-09-08 22:01 UTCEPSS rescoreEPSS 0.2% · 15th percentile
  34. 2026-09-07 23:59 UTCEG score recompute
  35. 2026-09-07 16:01 UTCEPSS rescoreEPSS 0.2% · 15th percentile
  36. 2026-09-06 13:47 UTCEPSS rescoreEPSS 0.2% · 15th percentile
  37. 2026-09-05 20:25 UTCEG score recompute
  38. 2026-09-04 05:06 UTCEPSS rescoreEPSS 0.2% · 15th percentile
  39. 2026-09-02 14:12 UTCEPSS rescoreEPSS 0.2% · 15th percentile
  40. 2026-09-01 13:54 UTCEPSS rescoreEPSS 0.2% · 15th percentile
  41. 2026-09-01 04:40 UTCEPSS rescoreEPSS 0.2% · 15th percentile
  42. 2026-08-31 05:14 UTCEG score recompute
  43. 2026-08-30 19:17 UTCEPSS rescoreEPSS 0.2% · 15th percentile
  44. 2026-08-30 03:14 UTCEG score recompute
  45. 2026-08-30 01:22 UTCEPSS rescoreEPSS 0.2% · 15th percentile
  46. 2026-08-28 21:41 UTCEPSS rescoreEPSS 0.2% · 15th percentile
  47. 2026-08-27 14:25 UTCEPSS rescoreEPSS 0.2% · 15th percentile
  48. 2026-08-27 13:51 UTCEG score recompute
  49. 2026-08-26 14:46 UTCEPSS rescoreEPSS 0.2% · 15th percentile
  50. 2026-08-26 11:55 UTCEG score recompute
  51. 2026-08-25 13:49 UTCEPSS rescoreEPSS 0.2% · 15th percentile
  52. 2026-08-25 09:47 UTCEG score recompute
  53. 2026-08-23 05:15 UTCEG score recompute
  54. 2026-08-23 00:19 UTCEPSS rescoreEPSS 0.2% · 16th percentile
  55. 2026-08-22 03:18 UTCEG score recompute
  56. 2026-08-21 23:49 UTCEPSS rescoreEPSS 0.2% · 16th percentile
  57. 2026-08-21 01:21 UTCEG score recompute
  58. 2026-08-20 22:55 UTCEPSS rescoreEPSS 0.2% · 16th percentile
  59. 2026-08-19 23:25 UTCEG score recompute
  60. 2026-08-19 17:04 UTCEPSS rescoreEPSS 0.2% · 16th percentile
  61. 2026-08-18 20:24 UTCEG score recompute
  62. 2026-08-18 19:30 UTCEG score recompute
  63. 2026-08-18 18:25 UTCEG score recompute
  64. 2026-07-30 19:08 UTCEG score recompute
  65. 2026-07-26 11:17 UTCEG score recompute
  66. 2026-07-23 03:19 UTCEG score recompute
  67. 2026-07-17 22:00 UTCEG score recompute

Frequently asked(5)

What is CVE-2026-54570?
CVE-2026-54570 is a medium-severity vulnerability; its CVE record was published on July 17, 2026. AngleSharp is a .NET library for parsing angle bracket based hyper-texts. Prior to 1.5.0, MathAnnotationXmlElement in AngleSharp/Mathml/Dom/Internal/MathAnnotationXmlElement.cs is not treated as an HTML integration point when its encoding attribute is text/html or application/xhtml+xml, causing…
When was the CVE record for CVE-2026-54570 published?
The CVE record for CVE-2026-54570 was published on July 17, 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 September 18, 2026; the record at its source may have been updated since.
Is CVE-2026-54570 actively exploited?
CVE-2026-54570 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.3% probability of exploitation in the next 30 days (26th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-54570?
CVE-2026-54570 has a CVSS base score of 6.9 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-54570?
A fix for CVE-2026-54570 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-54570 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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