CVE-2026-2783

HIGHNVD 7.57.5
EchelonGraph scoreMEDIUM confidence

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

Score 7.5 from GitHub Security Advisory (severity: HIGH) published 2026-02-24. NVD baseline CVSS 7.5; 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
7.5EG
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: 0.5%CVSS: 7.5Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

Information disclosure due to JIT miscompilation in the JavaScript Engine: JIT component. This vulnerability was fixed in Firefox 148, Firefox ESR 140.8, Thunderbird 148, and Thunderbird 140.8.

CVSS v3
7.5
EG Score
7.5HIGHmedium confidence
EG Risk
34
EG Risk 34/100

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)
Severity75% × 45%
Impact severity (EG Severity): CVSS 7.5 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 every mission impact level.
Exploitation none (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
0.5%
EPSS %ILE
39th
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 (7.5): severity, escalated by confirmed exploitation. This CVE's 7.5 is its impact severity (EG Severity), not escalated.

EG Severity
7.5 HIGHCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
EG Likelihood
0.5% within 30 daysSource: FIRST EPSS. 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 every mission impact level.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 every mission impact level.

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

Exploitation none (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

February 24, 2026

Last Modified

June 17, 2026

Advisory Details (5)

Auto-updated Jun 10, 2026
Patch available.
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 148 — Mozilla

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

2010943 - (CVE-2026-2783) Assertion failure: payload->toStackSlot()->width() == LStackSlot::width(LDefinition::GENERAL), at jit/shared/CodeGenerator-shared.cpp:603

https://bugzilla.mozilla.org/show_bug.cgi?id=2010943

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.el7_92026-03-09redhat
redhatthunderbird-0:140.8.0-1.el8_82026-03-09redhat
redhatthunderbird-0:140.8.0-1.el9_22026-03-09redhat
redhatthunderbird-0:140.8.0-1.el9_42026-03-09redhat
redhatthunderbird-0:140.8.0-1.el9_02026-03-09redhat
redhatfirefox-0:140.8.0-2.el10_02026-03-09redhat
redhatthunderbird-0:140.8.0-1.el9_62026-03-09redhat
redhatthunderbird-0:140.8.0-1.el8_62026-03-09redhat
redhatthunderbird-0:140.8.0-2.el8_42026-03-09redhat
redhatfirefox-0:140.8.0-2.el9_62026-03-02redhat
redhatfirefox-0:140.8.0-2.el9_42026-03-02redhat
redhatfirefox-0:140.8.0-2.el8_42026-03-02redhat
redhatfirefox-0:140.8.0-2.el8_22026-03-02redhat
redhatthunderbird-0:140.8.0-2.el10_12026-03-02redhat
redhatfirefox-0:140.8.0-2.el8_82026-03-02redhat
redhatthunderbird-0:140.8.0-1.el9_72026-03-02redhat
redhatthunderbird-0:140.8.0-1.el8_102026-03-02redhat
redhatfirefox-0:140.8.0-2.el8_62026-03-02redhat
redhatfirefox-0:140.8.0-2.el9_02026-03-02redhat
redhatfirefox-0:140.8.0-2.el8_102026-02-25redhat
redhatfirefox-0:140.8.0-2.el9_72026-02-25redhat
redhatfirefox-0:140.8.0-2.el10_12026-02-25redhat

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(2)

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

Additional Vendor Advisories

(5)

Data Freshness Timeline

(refreshed 11× in last 7d / 35× 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 95 of 250 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. 5 repeat rows among the latest 100 are merged into the row they repeat. The 155 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-10-23 16:31 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  2. 2026-10-22 16:34 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  3. 2026-10-21 16:32 UTCEPSS rescoreEPSS 0.4% · 35th percentile
  4. 2026-10-20 16:32 UTCEPSS rescoreEPSS 0.4% · 34th percentile
  5. 2026-10-19 16:31 UTCEPSS rescoreEPSS 0.4% · 34th percentile
  6. 2026-10-18 16:31 UTCEPSS rescoreEPSS 0.4% · 34th percentile
  7. 2026-10-18 03:51 UTCEG score recompute
  8. 2026-10-17 16:33 UTCEPSS rescoreEPSS 0.4% · 34th percentile
  9. 2026-10-17 16:24 UTCEG score recompute
  10. 2026-10-17 16:24 UTCVendor advisory
  11. 2026-10-17 16:23 UTCGHSA enrichmentGHSA-7xqm-gm4h-p23x · GitHub severity HIGH · GitHub CVSS 7.5
  12. 2026-10-16 16:41 UTCEPSS rescoreEPSS 0.4% · 34th percentile
  13. 2026-10-15 16:31 UTCEPSS rescoreEPSS 0.4% · 34th percentile
  14. 2026-10-14 16:32 UTCEPSS rescoreEPSS 0.4% · 34th percentile
  15. 2026-10-13 16:34 UTCEPSS rescoreEPSS 0.4% · 34th percentile
  16. 2026-10-12 16:34 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  17. 2026-10-12 16:17 UTCEG score recompute
  18. 2026-10-11 19:59 UTCEG score recompute
  19. 2026-10-11 17:12 UTCEG score recompute
  20. 2026-10-11 14:43 UTCEG score recompute
  21. 2026-10-11 13:48 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  22. 2026-10-10 20:00 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  23. 2026-10-09 20:07 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  24. 2026-10-09 06:55 UTCOSV refresh
  25. 2026-10-08 17:12 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
Show 70 more
  1. 2026-10-07 23:47 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  2. 2026-10-06 15:17 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  3. 2026-10-05 17:42 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  4. 2026-10-04 23:21 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  5. 2026-10-03 14:25 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  6. 2026-10-01 19:49 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  7. 2026-09-30 15:03 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  8. 2026-09-28 13:51 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  9. 2026-09-26 15:58 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  10. 2026-09-26 00:26 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  11. 2026-09-20 20:15 UTCEPSS rescoreEPSS 0.3% · 21st percentile
  12. 2026-09-19 13:33 UTCOSV refresh
  13. 2026-09-18 19:27 UTCEPSS rescoreEPSS 0.3% · 21st percentile
  14. 2026-09-17 19:30 UTCEPSS rescoreEPSS 0.3% · 21st percentile
  15. 2026-09-16 14:08 UTCEPSS rescoreEPSS 0.3% · 21st percentile
  16. 2026-09-16 05:15 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  17. 2026-09-13 16:47 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  18. 2026-09-12 15:01 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  19. 2026-09-11 14:52 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  20. 2026-09-10 09:34 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  21. 2026-09-08 22:00 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  22. 2026-09-07 16:01 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  23. 2026-09-06 13:47 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  24. 2026-09-04 05:06 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  25. 2026-09-02 14:11 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  26. 2026-09-01 13:53 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  27. 2026-09-01 04:39 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  28. 2026-08-31 17:04 UTCOSV refresh
  29. 2026-08-30 19:17 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  30. 2026-08-30 01:22 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  31. 2026-08-28 21:41 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  32. 2026-08-27 14:25 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  33. 2026-08-26 14:46 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  34. 2026-08-25 13:49 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  35. 2026-08-24 14:17 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  36. 2026-08-23 00:19 UTCEPSS rescoreEPSS 0.3% · 21st percentile
  37. 2026-08-21 23:49 UTCEPSS rescoreEPSS 0.3% · 21st percentile
  38. 2026-08-20 22:55 UTCEPSS rescoreEPSS 0.3% · 21st percentile
  39. 2026-08-19 17:03 UTCEPSS rescoreEPSS 0.3% · 21st percentile
  40. 2026-08-18 13:48 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  41. 2026-08-17 13:47 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  42. 2026-08-16 14:56 UTCEPSS rescoreEPSS 0.3% · 21st percentile
  43. 2026-08-16 02:14 UTCEPSS rescoreEPSS 0.3% · 21st percentile
  44. 2026-08-15 01:30 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  45. 2026-08-14 21:28 UTCVendor advisory
  46. 2026-08-14 21:28 UTCGHSA enrichmentGHSA-7xqm-gm4h-p23x · GitHub severity HIGH · GitHub CVSS 7.5
  47. 2026-08-14 09:07 UTCEG score recompute
  48. 2026-08-14 09:07 UTCVendor advisory
  49. 2026-08-14 09:07 UTCGHSA enrichmentGHSA-7xqm-gm4h-p23x · GitHub severity HIGH · GitHub CVSS 7.5
  50. 2026-08-13 22:00 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  51. 2026-08-13 01:07 UTCEG score recompute
  52. 2026-08-13 01:07 UTCVendor advisory
  53. 2026-08-13 01:07 UTCGHSA enrichmentGHSA-7xqm-gm4h-p23x · GitHub severity HIGH · GitHub CVSS 7.5
  54. 2026-08-12 13:50 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  55. 2026-08-12 00:54 UTCEG score recompute
  56. 2026-08-12 00:54 UTCVendor advisory
  57. 2026-08-12 00:54 UTCGHSA enrichmentGHSA-7xqm-gm4h-p23x · GitHub severity HIGH · GitHub CVSS 7.5
  58. 2026-08-11 06:37 UTCEG score recompute
  59. 2026-08-11 06:37 UTCVendor advisory
  60. 2026-08-11 06:37 UTCGHSA enrichmentGHSA-7xqm-gm4h-p23x · GitHub severity HIGH · GitHub CVSS 7.5
  61. 2026-08-11 00:00 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  62. 2026-08-10 08:54 UTCVendor advisory
  63. 2026-08-10 08:54 UTCGHSA enrichmentGHSA-7xqm-gm4h-p23x · GitHub severity HIGH · GitHub CVSS 7.5
  64. 2026-08-09 20:38 UTCEG score recompute
  65. 2026-08-09 20:38 UTCVendor advisory
  66. 2026-08-09 20:38 UTCGHSA enrichmentGHSA-7xqm-gm4h-p23x · GitHub severity HIGH · GitHub CVSS 7.5
  67. 2026-08-09 13:46 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  68. 2026-08-09 08:45 UTCEG score recompute
  69. 2026-08-09 08:45 UTCVendor advisory
  70. 2026-08-09 08:45 UTCGHSA enrichmentGHSA-7xqm-gm4h-p23x · GitHub severity HIGH · GitHub CVSS 7.5

Frequently asked(5)

What is CVE-2026-2783?
CVE-2026-2783 is a high-severity vulnerability; its CVE record was published on February 24, 2026. Information disclosure due to JIT miscompilation in the JavaScript Engine: JIT component. This vulnerability was fixed in Firefox 148, Firefox ESR 140.8, Thunderbird 148, and Thunderbird 140.8.
When was the CVE record for CVE-2026-2783 published?
The CVE record for CVE-2026-2783 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 June 17, 2026; the record at its source may have been updated since.
Is CVE-2026-2783 actively exploited?
CVE-2026-2783 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.5% probability of exploitation in the next 30 days (39th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-2783?
CVE-2026-2783 has a CVSS v3 base score of 7.5 (NVD).
How do I remediate CVE-2026-2783?
A fix for CVE-2026-2783 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-2783 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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