CVE-2020-0878

CRITICALNVD 4.29.0
EchelonGraph scoreHIGH confidence

“▲” beside the score: it is higher than NVD's CVSS score.

Score elevated to 9.0 because this CVE is listed on the CISA Known Exploited Vulnerabilities catalog (added 2021-11-03), indicating real-world exploitation has been confirmed by US federal agencies. NVD baseline CVSS 4.2 retained for reference. The 9.0 is the floor for confirmed exploitation, not an impact rating: this CVE's impact severity (EG Severity) is CVSS 4.2 MEDIUM under GitHub Security Advisory CVSS. Confidence: HIGH.

Triggered by: CISA KEV (actively exploited)
Sources: CISA Known Exploited Vulnerabilities catalog, EPSS, GitHub Security Advisory, NVD CVSS v3
Trending — 4 sources updated this weekExploited in the wild

Also known asEUVD-2020-2346 (ENISA EUVD) · GHSA-6j33-6rqj-fh2m (GitHub Security Advisories)Source: ENISA EUVD

9.0EG
EchelonGraph verdictPatch nowTreat as an emergency — this is being exploited.
  • Actively exploited in the wild (CISA-KEV) — the reason this is sooner than the SSVC decision on this page at low or medium mission impact
CISA-KEV: ExploitedEPSS PROB: 2.7%CVSS: 4.2Exploit: No code on recordExposed services: Not assessed

A fix is available — apply it.

A remote code execution vulnerability exists in the way that Microsoft browsers access objects in memory. The vulnerability could corrupt memory in a way that could allow an attacker to execute arbitrary code in the context of the current user. An attacker who successfully exploited the vulnerability could gain the same user rights as the current user. If the current user is logged on with administrative user rights, the attacker could take control of an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. An attacker could host a specially crafted website that is designed to exploit the vulnerability through Microsoft browsers, and then convince a user to view the website. The attacker could also take advantage of compromised websites, or websites that accept or host user-provided content or advertisements, by adding specially crafted content that could exploit the vulnerability. In all cases, however, an attacker would have no way to force users to view the attacker-controlled content. Instead, an attacker would have to convince users to take action, typically via an enticement in email or instant message, or by getting them to open an email attachment. The security update addresses the vulnerability by modifying how Microsoft browsers handle objects in memory.

CVSS v3
4.2
EG Score
9.0CRITICALhigh confidence
EG Risk
59
EG Risk 59/100

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)
Severity42% × 45%
Impact severity (EG Severity): CVSS 4.2 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation100% × 40%
Fixed at 100% for a CISA KEV listing: EchelonGraph's rule.
Automatability0% × 15%
CISA's SSVC Automatable value: no (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at low, Attend at medium and Act at high mission impact.
Exploitation active (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 at low, sooner than that at medium and as soon as possible at high mission impact.
EPSS PROB
2.7%
EPSS %ILE
85th
KEV
⚠ Exploited

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

The EG score (9.0): severity, escalated by confirmed exploitation. This CVE's 9.0 is the CISA KEV floor for confirmed exploitation, not an impact rating: its impact severity (EG Severity) is CVSS 4.2 MEDIUM.

EG Severity
4.2 MEDIUMCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
EG Likelihood
2.7% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-11-01). FIRST's exploitation probability, not an EchelonGraph model.
Confirmed exploitation
CISA KEV and EG-KEV Tier 1 (exploited in the wild)Reported apart from the likelihood: an observed fact, not a probability.
EG Priority
SSVC Attend at medium mission impactTrack at low, Attend at medium and Act at high mission impact.CISA BOD 26-04: 3 days & forensic triage if the affected system is publicly exposed; 14 days if it is not.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, Attend at medium and Act at high mission impact.

A fix is available. Apply it within your standard update timelines at low, sooner than that at medium and as soon as possible at high mission impact.

Exploitation active (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)3 days & forensic triage if the affected system is publicly exposed; 14 days if it is not.

The score's inputs: In CISA KEV yes (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

CISA required action“Apply updates per vendor instructions.”

Quoted verbatim from CISA's Known Exploited Vulnerabilities catalog. CISA directs it at US federal civilian executive branch agencies under Binding Operational Directive (BOD) 26-04, which replaced BOD 22-01 on 10 June 2026; it is not EchelonGraph's advice. CISA's notes: https://nvd.nist.gov/vuln/detail/CVE-2020-0878

Published

September 11, 2020

Last Modified

February 23, 2026

Advisory Details (2)

Auto-updated Oct 27, 2026
⚠️ Actively exploited (CISA KEV, CISA Vulnrichment). Patch available. Sources: microsoft, cisa.
CISA🔴 Active Exploitation

Known Exploited Vulnerabilities Catalog | CISA

Known Exploited Vulnerabilities Catalog | CISA. Listed in CISA Known Exploited Vulnerabilities catalog.

https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2020-0878
Microsoft

Security Update Guide - Microsoft Security Response Center

https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-0878

Vendor Advisories for CVE-2020-0878(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 25× in last 7d / 193× 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.

Showing the most recent 100 of 1,863 refreshes on record for this CVE.

A repeat, a row identical to one the same pipeline wrote less than 10 seconds earlier, is not a separate refresh and is not counted. None are among the latest 100 rows. The 1,763 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-11-02 16:36 UTCEPSS rescoreEPSS 2.7% · 85th percentile
  2. 2026-11-02 06:35 UTCEG score recompute
  3. 2026-11-02 06:35 UTCVendor advisory
  4. 2026-11-02 06:34 UTCGHSA enrichmentGHSA-6j33-6rqj-fh2m · GitHub severity HIGH · GitHub CVSS 4.2
  5. 2026-11-01 16:29 UTCEPSS rescoreEPSS 2.7% · 85th percentile
  6. 2026-11-01 06:34 UTCEG score recompute
  7. 2026-11-01 06:34 UTCVendor advisory
  8. 2026-11-01 06:34 UTCGHSA enrichmentGHSA-6j33-6rqj-fh2m · GitHub severity HIGH · GitHub CVSS 4.2
  9. 2026-10-31 16:28 UTCEPSS rescoreEPSS 2.7% · 85th percentile
  10. 2026-10-31 06:33 UTCEG score recompute
  11. 2026-10-31 06:33 UTCVendor advisory
  12. 2026-10-31 06:33 UTCGHSA enrichmentGHSA-6j33-6rqj-fh2m · GitHub severity HIGH · GitHub CVSS 4.2
  13. 2026-10-30 16:29 UTCEPSS rescoreEPSS 2.7% · 85th percentile
  14. 2026-10-30 06:32 UTCEG score recompute
  15. 2026-10-30 06:32 UTCVendor advisory
  16. 2026-10-30 06:32 UTCGHSA enrichmentGHSA-6j33-6rqj-fh2m · GitHub severity HIGH · GitHub CVSS 4.2
  17. 2026-10-29 16:28 UTCEPSS rescoreEPSS 2.7% · 85th percentile
  18. 2026-10-29 06:31 UTCEG score recompute
  19. 2026-10-29 06:31 UTCGHSA enrichmentGHSA-6j33-6rqj-fh2m · GitHub severity HIGH · GitHub CVSS 4.2
  20. 2026-10-28 16:27 UTCEPSS rescoreEPSS 2.7% · 85th percentile
  21. 2026-10-28 06:31 UTCEG score recompute
  22. 2026-10-28 06:31 UTCGHSA enrichmentGHSA-6j33-6rqj-fh2m · GitHub severity HIGH · GitHub CVSS 4.2
  23. 2026-10-27 16:27 UTCEPSS rescoreEPSS 2.7% · 85th percentile
  24. 2026-10-27 06:31 UTCEG score recompute
  25. 2026-10-27 06:31 UTCGHSA enrichmentGHSA-6j33-6rqj-fh2m · GitHub severity HIGH · GitHub CVSS 4.2
Show 75 more
  1. 2026-10-26 16:27 UTCEPSS rescoreEPSS 2.7% · 85th percentile
  2. 2026-10-26 06:29 UTCVendor advisory
  3. 2026-10-26 06:29 UTCGHSA enrichmentGHSA-6j33-6rqj-fh2m · GitHub severity HIGH · GitHub CVSS 4.2
  4. 2026-10-25 18:54 UTCEG score recompute
  5. 2026-10-25 16:28 UTCEPSS rescoreEPSS 2.7% · 85th percentile
  6. 2026-10-25 06:28 UTCEG score recompute
  7. 2026-10-25 06:28 UTCVendor advisory
  8. 2026-10-25 06:28 UTCGHSA enrichmentGHSA-6j33-6rqj-fh2m · GitHub severity HIGH · GitHub CVSS 4.2
  9. 2026-10-24 16:28 UTCEPSS rescoreEPSS 2.7% · 85th percentile
  10. 2026-10-24 06:28 UTCEG score recompute
  11. 2026-10-24 06:28 UTCGHSA enrichmentGHSA-6j33-6rqj-fh2m · GitHub severity HIGH · GitHub CVSS 4.2
  12. 2026-10-23 16:27 UTCEPSS rescoreEPSS 2.7% · 85th percentile
  13. 2026-10-23 06:27 UTCEG score recompute
  14. 2026-10-23 06:27 UTCVendor advisory
  15. 2026-10-23 06:27 UTCGHSA enrichmentGHSA-6j33-6rqj-fh2m · GitHub severity HIGH · GitHub CVSS 4.2
  16. 2026-10-22 16:28 UTCEPSS rescoreEPSS 2.7% · 85th percentile
  17. 2026-10-22 06:26 UTCEG score recompute
  18. 2026-10-22 06:26 UTCVendor advisory
  19. 2026-10-22 06:26 UTCGHSA enrichmentGHSA-6j33-6rqj-fh2m · GitHub severity HIGH · GitHub CVSS 4.2
  20. 2026-10-21 16:28 UTCEPSS rescoreEPSS 2.7% · 85th percentile
  21. 2026-10-21 06:22 UTCEG score recompute
  22. 2026-10-21 06:22 UTCVendor advisory
  23. 2026-10-21 06:22 UTCGHSA enrichmentGHSA-6j33-6rqj-fh2m · GitHub severity HIGH · GitHub CVSS 4.2
  24. 2026-10-20 16:28 UTCEPSS rescoreEPSS 2.7% · 85th percentile
  25. 2026-10-20 06:20 UTCEG score recompute
  26. 2026-10-20 06:20 UTCVendor advisory
  27. 2026-10-20 06:20 UTCGHSA enrichmentGHSA-6j33-6rqj-fh2m · GitHub severity HIGH · GitHub CVSS 4.2
  28. 2026-10-19 16:27 UTCEPSS rescoreEPSS 2.7% · 85th percentile
  29. 2026-10-19 06:18 UTCEG score recompute
  30. 2026-10-19 06:18 UTCVendor advisory
  31. 2026-10-19 06:18 UTCGHSA enrichmentGHSA-6j33-6rqj-fh2m · GitHub severity HIGH · GitHub CVSS 4.2
  32. 2026-10-18 16:28 UTCEPSS rescoreEPSS 2.7% · 85th percentile
  33. 2026-10-18 06:16 UTCEG score recompute
  34. 2026-10-18 06:16 UTCVendor advisory
  35. 2026-10-18 06:16 UTCGHSA enrichmentGHSA-6j33-6rqj-fh2m · GitHub severity HIGH · GitHub CVSS 4.2
  36. 2026-10-17 16:28 UTCEPSS rescoreEPSS 2.7% · 85th percentile
  37. 2026-10-17 06:14 UTCEG score recompute
  38. 2026-10-17 06:13 UTCGHSA enrichmentGHSA-6j33-6rqj-fh2m · GitHub severity HIGH · GitHub CVSS 4.2
  39. 2026-10-16 16:32 UTCEPSS rescoreEPSS 2.7% · 85th percentile
  40. 2026-10-16 06:11 UTCEG score recompute
  41. 2026-10-16 06:11 UTCGHSA enrichmentGHSA-6j33-6rqj-fh2m · GitHub severity HIGH · GitHub CVSS 4.2
  42. 2026-10-15 16:27 UTCEPSS rescoreEPSS 2.7% · 85th percentile
  43. 2026-10-15 06:10 UTCEG score recompute
  44. 2026-10-15 06:10 UTCVendor advisory
  45. 2026-10-15 06:10 UTCGHSA enrichmentGHSA-6j33-6rqj-fh2m · GitHub severity HIGH · GitHub CVSS 4.2
  46. 2026-10-14 16:28 UTCEPSS rescoreEPSS 2.7% · 85th percentile
  47. 2026-10-14 06:07 UTCEG score recompute
  48. 2026-10-14 06:07 UTCGHSA enrichmentGHSA-6j33-6rqj-fh2m · GitHub severity HIGH · GitHub CVSS 4.2
  49. 2026-10-13 16:28 UTCEPSS rescoreEPSS 2.7% · 85th percentile
  50. 2026-10-13 06:04 UTCVendor advisory
  51. 2026-10-13 06:04 UTCGHSA enrichmentGHSA-6j33-6rqj-fh2m · GitHub severity HIGH · GitHub CVSS 4.2
  52. 2026-10-12 19:49 UTCEG score recompute
  53. 2026-10-12 16:29 UTCEPSS rescoreEPSS 2.7% · 85th percentile
  54. 2026-10-12 06:01 UTCVendor advisory
  55. 2026-10-12 06:01 UTCGHSA enrichmentGHSA-6j33-6rqj-fh2m · GitHub severity HIGH · GitHub CVSS 4.2
  56. 2026-10-12 01:56 UTCVendor advisory
  57. 2026-10-12 01:56 UTCGHSA enrichmentGHSA-6j33-6rqj-fh2m · GitHub severity HIGH · GitHub CVSS 4.2
  58. 2026-10-11 21:53 UTCEG score recompute
  59. 2026-10-11 21:53 UTCVendor advisory
  60. 2026-10-11 21:52 UTCGHSA enrichmentGHSA-6j33-6rqj-fh2m · GitHub severity HIGH · GitHub CVSS 4.2
  61. 2026-10-11 17:48 UTCEG score recompute
  62. 2026-10-11 17:48 UTCVendor advisory
  63. 2026-10-11 17:48 UTCGHSA enrichmentGHSA-6j33-6rqj-fh2m · GitHub severity HIGH · GitHub CVSS 4.2
  64. 2026-10-11 13:42 UTCEPSS rescoreEPSS 2.7% · 85th percentile
  65. 2026-10-11 13:42 UTCEG score recompute
  66. 2026-10-11 13:42 UTCVendor advisory
  67. 2026-10-11 13:42 UTCGHSA enrichmentGHSA-6j33-6rqj-fh2m · GitHub severity HIGH · GitHub CVSS 4.2
  68. 2026-10-11 09:37 UTCVendor advisory
  69. 2026-10-11 09:37 UTCGHSA enrichmentGHSA-6j33-6rqj-fh2m · GitHub severity HIGH · GitHub CVSS 4.2
  70. 2026-10-11 05:35 UTCVendor advisory
  71. 2026-10-11 05:35 UTCGHSA enrichmentGHSA-6j33-6rqj-fh2m · GitHub severity HIGH · GitHub CVSS 4.2
  72. 2026-10-11 01:32 UTCVendor advisory
  73. 2026-10-11 01:31 UTCGHSA enrichmentGHSA-6j33-6rqj-fh2m · GitHub severity HIGH · GitHub CVSS 4.2
  74. 2026-10-10 21:28 UTCEG score recompute
  75. 2026-10-10 21:28 UTCVendor advisory

Frequently asked(6)

What is CVE-2020-0878?
CVE-2020-0878 is a critical-severity vulnerability; its CVE record was published on September 11, 2020. <p>A remote code execution vulnerability exists in the way that Microsoft browsers access objects in memory. The vulnerability could corrupt memory in a way that could allow an attacker to execute arbitrary code in the context of the current user. An attacker who successfully exploited the…
When was CVE-2020-0878 made public?
CVE-2020-0878 was made public on September 8, 2020: that is the date its CVE record's CNA, Microsoft Corporation, gives for when the vulnerability was made public. The CVE record itself was published on September 11, 2020. EchelonGraph's copy of the record carries a last-modified date of February 23, 2026; the record at its source may have been updated since.
Is CVE-2020-0878 actively exploited?
Yes. CISA added CVE-2020-0878 to the Known Exploited Vulnerabilities catalog on November 3, 2021, affecting Microsoft Edge and Internet Explorer. KEV listing indicates confirmed exploitation in the wild; this CVE warrants immediate attention. A fix is available. Apply it.
What is the CVSS score of CVE-2020-0878?
CVE-2020-0878 has a CVSS v3 base score of 4.2 (NVD). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 9.0 (CRITICAL).
Which products are affected by CVE-2020-0878?
CVE-2020-0878 affects Microsoft Edge and Internet Explorer.
How do I remediate CVE-2020-0878?
A fix for CVE-2020-0878 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2020-0878 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

Explore the affected products and dependency analysis for CVE-2020-0878

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