CVE-2026-2793

CRITICALNVD 9.89.8
EchelonGraph scoreMEDIUM confidence

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

Score 9.8 from GitHub Security Advisory (severity: CRITICAL) published 2026-02-24. NVD baseline CVSS 9.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: EPSS, GitHub Security Advisory, NVD CVSS v3
Trending — 4 sources updated this week

Also known asEUVD-2026-8445 (ENISA EUVD) · GHSA-48q6-99pr-mcvm (GitHub Security Advisories)Source: ENISA EUVD

9.8EG
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: 9.8Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

Memory safety bugs present in Firefox ESR 115.32, Firefox ESR 140.7, Thunderbird ESR 140.7, Firefox 147 and Thunderbird 147. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 148, Firefox ESR 115.33, Firefox ESR 140.8, Thunderbird 148, and Thunderbird 140.8.

CVSS v3
9.8
EG Score
9.8CRITICALmedium confidence
EG Risk
44
EG Risk 44/100

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)
Severity98% × 45%
Impact severity (EG Severity): CVSS 9.8 of 10. Never the KEV-floored or EPSS-lifted EG Score.
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
31st
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 (9.8): severity, escalated by confirmed exploitation. This CVE's 9.8 is its impact severity (EG Severity), not escalated.

EG Severity
9.8 CRITICALCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
EG Likelihood
0.4% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-31). 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: 14 days if the affected system is publicly exposed; Fix on system upgrade 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 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.

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

February 24, 2026

Last Modified

July 15, 2026

Advisory Details (10)

Auto-updated Oct 31, 2026
Patch available. Sources: redhat.
Red HatMentions a patch (unverified)

Affected: Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support and Red Hat Enterprise Linux 8.4 Extended Update Support

https://access.redhat.com/errata/RHSA-2026:3491
Red HatMentions a patch (unverified)

Affected: Red Hat Enterprise Linux 10.

https://access.redhat.com/errata/RHSA-2026:3361
Red HatMentions a patch (unverified)

Affected: Red Hat Enterprise Linux 9.

https://access.redhat.com/errata/RHSA-2026:3339
Red HatMentions a patch (unverified)

Affected: Red Hat Enterprise Linux 8.

https://access.redhat.com/errata/RHSA-2026:3338
Web page

Security Vulnerabilities fixed in Thunderbird 140.8 — Mozilla

https://www.mozilla.org/security/advisories/mfsa2026-17/
Web page

Security Vulnerabilities fixed in Thunderbird 148 — Mozilla

https://www.mozilla.org/security/advisories/mfsa2026-16/
Web page

Security Vulnerabilities fixed in Firefox ESR 140.8 — Mozilla

https://www.mozilla.org/security/advisories/mfsa2026-15/
Web page

Security Vulnerabilities fixed in Firefox ESR 115.33 — Mozilla

https://www.mozilla.org/security/advisories/mfsa2026-14/
Web page

Security Vulnerabilities fixed in Firefox 148 — Mozilla

https://www.mozilla.org/security/advisories/mfsa2026-13/

Patch Availability(25)

Vendor / EcosystemFix (by version range) / PatchReleasedSource
redhatthunderbird-0:140.8.0-1.el8_22026-03-12redhat
redhatthunderbird-0:140.8.0-2.el10_02026-03-11redhat
redhatfirefox-0:140.8.0-2.el9_22026-03-10redhat
redhatfirefox-0:140.8.0-2.el10_02026-03-09redhat
redhatthunderbird-0:140.8.0-1.el9_42026-03-09redhat
redhatthunderbird-0:140.8.0-1.el9_22026-03-09redhat
redhatfirefox-0:140.8.0-2.el7_92026-03-09redhat
redhatthunderbird-0:140.8.0-2.el8_42026-03-09redhat
redhatthunderbird-0:140.8.0-1.el8_82026-03-09redhat
redhatthunderbird-0:140.8.0-1.el9_02026-03-09redhat
redhatthunderbird-0:140.8.0-1.el8_62026-03-09redhat
redhatthunderbird-0:140.8.0-1.el9_62026-03-09redhat
redhatfirefox-0:140.8.0-2.el9_62026-03-02redhat
redhatthunderbird-0:140.8.0-2.el10_12026-03-02redhat
redhatfirefox-0:140.8.0-2.el8_82026-03-02redhat
redhatfirefox-0:140.8.0-2.el8_42026-03-02redhat
redhatfirefox-0:140.8.0-2.el8_22026-03-02redhat
redhatfirefox-0:140.8.0-2.el9_42026-03-02redhat
redhatthunderbird-0:140.8.0-1.el9_72026-03-02redhat
redhatfirefox-0:140.8.0-2.el8_62026-03-02redhat
redhatthunderbird-0:140.8.0-1.el8_102026-03-02redhat
redhatfirefox-0:140.8.0-2.el9_02026-03-02redhat
redhatfirefox-0:140.8.0-2.el10_12026-02-25redhat
redhatfirefox-0:140.8.0-2.el8_102026-02-25redhat
redhatfirefox-0:140.8.0-2.el9_72026-02-25redhat

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Affected Packages

(8 across 4 ecosystems)
Debian:11(2)
PackageVulnerable rangeFix by version rangeDependents
firefox-esr102.1.0esr-1 ... 91.9.1esr-1~deb9u1 (251 versions)
  • every version up to 140.8.0esr-1~deb11u1: fixed in 140.8.0esr-1~deb11u1
—
thunderbird1:102.0.1-1 ... 1:91.9.0-1~deb9u1 (302 versions)
  • every version up to 1:140.8.0esr-1~deb11u1: fixed in 1:140.8.0esr-1~deb11u1
—
Debian:12(2)
PackageVulnerable rangeFix by version rangeDependents
firefox-esr102.11.0esr-1 ... 140.8.0esr-1~deb11u1 (158 versions)
  • every version up to 140.8.0esr-1~deb12u1: fixed in 140.8.0esr-1~deb12u1
—
thunderbird1:102.11.0-1 ... 1:140.8.0esr-1~deb11u1 (187 versions)
  • every version up to 1:140.8.0esr-1~deb12u1: fixed in 1:140.8.0esr-1~deb12u1
—
Debian:13(2)
PackageVulnerable rangeFix by version rangeDependents
firefox-esr128.13.0esr-1 ... 140.8.0esr-1~deb12u1 (34 versions)
  • every version up to 140.8.0esr-1~deb13u1: fixed in 140.8.0esr-1~deb13u1
—
thunderbird1:128.13.0esr-1 ... 1:140.8.0esr-1~deb12u1 (43 versions)
  • every version up to 1:140.8.0esr-1~deb13u1: fixed in 1:140.8.0esr-1~deb13u1
—
Debian:14(2)
PackageVulnerable rangeFix by version rangeDependents
firefox-esr128.13.0esr-1 ... 140.8.0esr-1~deb13u1 (35 versions)
  • every version up to 140.8.0esr-1: fixed in 140.8.0esr-1
—
thunderbird1:128.13.0esr-1 ... 1:140.8.0esr-1~deb13u1 (44 versions)
  • every version up to 1:140.8.0esr-1: fixed in 1:140.8.0esr-1
—

Weakness Classification(1)

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

Additional Vendor Advisories

(5)

Data Freshness Timeline

(refreshed 25× in last 7d / 93× 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 99 of 346 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. 1 repeat row among the latest 100 is merged into the row it repeats. The 247 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-11-01 16:34 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  2. 2026-11-01 11:46 UTCEG score recompute
  3. 2026-11-01 11:46 UTCVendor advisory
  4. 2026-11-01 11:46 UTCGHSA enrichmentGHSA-48q6-99pr-mcvm · GitHub severity CRITICAL · GitHub CVSS 9.8
  5. 2026-10-31 16:32 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  6. 2026-10-31 09:27 UTCEG score recompute
  7. 2026-10-31 09:27 UTCVendor advisory
  8. 2026-10-31 09:27 UTCGHSA enrichmentGHSA-48q6-99pr-mcvm · GitHub severity CRITICAL · GitHub CVSS 9.8
  9. 2026-10-30 16:34 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  10. 2026-10-30 07:07 UTCEG score recompute
  11. 2026-10-30 07:07 UTCVendor advisory
  12. 2026-10-30 07:07 UTCGHSA enrichmentGHSA-48q6-99pr-mcvm · GitHub severity CRITICAL · GitHub CVSS 9.8
  13. 2026-10-29 16:33 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  14. 2026-10-29 04:47 UTCEG score recompute
  15. 2026-10-29 04:47 UTCVendor advisory
  16. 2026-10-29 04:47 UTCGHSA enrichmentGHSA-48q6-99pr-mcvm · GitHub severity CRITICAL · GitHub CVSS 9.8
  17. 2026-10-28 16:32 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  18. 2026-10-28 02:21 UTCEG score recompute
  19. 2026-10-28 02:21 UTCVendor advisory
  20. 2026-10-28 02:20 UTCGHSA enrichmentGHSA-48q6-99pr-mcvm · GitHub severity CRITICAL · GitHub CVSS 9.8
  21. 2026-10-27 16:31 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  22. 2026-10-26 23:59 UTCEG score recompute
  23. 2026-10-26 23:59 UTCVendor advisory
  24. 2026-10-26 23:59 UTCGHSA enrichmentGHSA-48q6-99pr-mcvm · GitHub severity CRITICAL · GitHub CVSS 9.8
  25. 2026-10-26 16:31 UTCEPSS rescoreEPSS 0.4% · 31st percentile
Show 74 more
  1. 2026-10-25 18:04 UTCEG score recompute
  2. 2026-10-25 18:04 UTCVendor advisory
  3. 2026-10-25 18:04 UTCGHSA enrichmentGHSA-48q6-99pr-mcvm · GitHub severity CRITICAL · GitHub CVSS 9.8
  4. 2026-10-25 16:32 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  5. 2026-10-25 14:38 UTCEG score recompute
  6. 2026-10-24 16:32 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  7. 2026-10-24 15:17 UTCEG score recompute
  8. 2026-10-24 15:17 UTCVendor advisory
  9. 2026-10-24 15:17 UTCGHSA enrichmentGHSA-48q6-99pr-mcvm · GitHub severity CRITICAL · GitHub CVSS 9.8
  10. 2026-10-23 16:31 UTCEPSS rescoreEPSS 0.7% · 52nd percentile
  11. 2026-10-23 12:58 UTCEG score recompute
  12. 2026-10-23 12:58 UTCVendor advisory
  13. 2026-10-23 12:57 UTCGHSA enrichmentGHSA-48q6-99pr-mcvm · GitHub severity CRITICAL · GitHub CVSS 9.8
  14. 2026-10-22 16:34 UTCEPSS rescoreEPSS 0.7% · 52nd percentile
  15. 2026-10-22 10:38 UTCEG score recompute
  16. 2026-10-22 10:38 UTCVendor advisory
  17. 2026-10-22 10:38 UTCGHSA enrichmentGHSA-48q6-99pr-mcvm · GitHub severity CRITICAL · GitHub CVSS 9.8
  18. 2026-10-21 16:32 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  19. 2026-10-21 08:16 UTCEG score recompute
  20. 2026-10-21 08:16 UTCVendor advisory
  21. 2026-10-21 08:16 UTCGHSA enrichmentGHSA-48q6-99pr-mcvm · GitHub severity CRITICAL · GitHub CVSS 9.8
  22. 2026-10-20 16:32 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  23. 2026-10-20 05:56 UTCEG score recompute
  24. 2026-10-20 05:56 UTCVendor advisory
  25. 2026-10-20 05:56 UTCGHSA enrichmentGHSA-48q6-99pr-mcvm · GitHub severity CRITICAL · GitHub CVSS 9.8
  26. 2026-10-19 16:31 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  27. 2026-10-19 03:35 UTCEG score recompute
  28. 2026-10-19 03:35 UTCVendor advisory
  29. 2026-10-19 03:34 UTCGHSA enrichmentGHSA-48q6-99pr-mcvm · GitHub severity CRITICAL · GitHub CVSS 9.8
  30. 2026-10-18 16:31 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  31. 2026-10-18 03:50 UTCEG score recompute
  32. 2026-10-18 01:12 UTCEG score recompute
  33. 2026-10-18 01:12 UTCVendor advisory
  34. 2026-10-18 01:12 UTCGHSA enrichmentGHSA-48q6-99pr-mcvm · GitHub severity CRITICAL · GitHub CVSS 9.8
  35. 2026-10-17 16:33 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  36. 2026-10-16 22:52 UTCEG score recompute
  37. 2026-10-16 22:52 UTCVendor advisory
  38. 2026-10-16 22:52 UTCGHSA enrichmentGHSA-48q6-99pr-mcvm · GitHub severity CRITICAL · GitHub CVSS 9.8
  39. 2026-10-16 16:41 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  40. 2026-10-15 19:53 UTCEG score recompute
  41. 2026-10-15 19:53 UTCVendor advisory
  42. 2026-10-15 19:52 UTCGHSA enrichmentGHSA-48q6-99pr-mcvm · GitHub severity CRITICAL · GitHub CVSS 9.8
  43. 2026-10-15 16:31 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  44. 2026-10-14 16:32 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  45. 2026-10-14 13:48 UTCEG score recompute
  46. 2026-10-14 13:48 UTCVendor advisory
  47. 2026-10-14 13:47 UTCGHSA enrichmentGHSA-48q6-99pr-mcvm · GitHub severity CRITICAL · GitHub CVSS 9.8
  48. 2026-10-13 16:34 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  49. 2026-10-13 11:09 UTCEG score recompute
  50. 2026-10-13 11:09 UTCVendor advisory
  51. 2026-10-13 11:09 UTCGHSA enrichmentGHSA-48q6-99pr-mcvm · GitHub severity CRITICAL · GitHub CVSS 9.8
  52. 2026-10-12 16:34 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  53. 2026-10-12 16:17 UTCEG score recompute
  54. 2026-10-12 08:49 UTCVendor advisory
  55. 2026-10-12 08:49 UTCGHSA enrichmentGHSA-48q6-99pr-mcvm · GitHub severity CRITICAL · GitHub CVSS 9.8
  56. 2026-10-11 19:59 UTCEG score recompute
  57. 2026-10-11 17:12 UTCEG score recompute
  58. 2026-10-11 14:43 UTCEG score recompute
  59. 2026-10-11 13:48 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  60. 2026-10-10 20:00 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  61. 2026-10-09 20:07 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  62. 2026-10-09 14:55 UTCOSV refresh
  63. 2026-10-08 17:12 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  64. 2026-10-07 23:47 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  65. 2026-10-06 15:17 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  66. 2026-10-05 17:42 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  67. 2026-10-04 23:21 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  68. 2026-10-03 14:25 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  69. 2026-10-01 19:49 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  70. 2026-09-30 15:03 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  71. 2026-09-28 13:51 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  72. 2026-09-26 15:58 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  73. 2026-09-26 00:26 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  74. 2026-09-20 20:15 UTCEPSS rescoreEPSS 0.3% · 24th percentile

Frequently asked(5)

What is CVE-2026-2793?
CVE-2026-2793 is a critical-severity vulnerability; its CVE record was published on February 24, 2026. Memory safety bugs present in Firefox ESR 115.32, Firefox ESR 140.7, Thunderbird ESR 140.7, Firefox 147 and Thunderbird 147. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This…
When was the CVE record for CVE-2026-2793 published?
The CVE record for CVE-2026-2793 was published on February 24, 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 July 15, 2026; the record at its source may have been updated since.
Is CVE-2026-2793 actively exploited?
CVE-2026-2793 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.4% probability of exploitation in the next 30 days (31st percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-2793?
CVE-2026-2793 has a CVSS v3 base score of 9.8 (NVD).
How do I remediate CVE-2026-2793?
A fix for CVE-2026-2793 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-2793 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-2793

Explore →

Is Your Infrastructure Affected by CVE-2026-2793?

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