CVE-2026-12289

HIGHPre-NVD 8.88.8
EchelonGraph scoreMEDIUM confidence

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

Score 8.8 from GitHub Security Advisory (severity: HIGH) published 2026-06-16. CISA-ADP (Vulnrichment) CVSS v3.1 baseline 8.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: CISA-ADP (Vulnrichment) CVSS v3.1, EPSS, GitHub Security Advisory
8.8EG
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: 8.8Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

Privilege escalation in the Graphics: WebRender component. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Firefox ESR 115.37, Thunderbird 152, and Thunderbird 140.12.

CVSS v3
8.8
EG Score
8.8HIGHmedium confidence
EG Risk
40
EG Risk 40/100

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed (value × EchelonGraph’s weight)
Severity88% × 45%
The EG Score, 8.8 of 10.
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

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.

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

June 16, 2026

Last Modified

July 15, 2026

Advisory Details (4)

Auto-updated Jun 16, 2026
Patch available.
Web page

Security Vulnerabilities fixed in Firefox ESR 115.37 — Mozilla

https://www.mozilla.org/security/advisories/mfsa2026-59/
Web page

Security Vulnerabilities fixed in Firefox ESR 140.12 — Mozilla

https://www.mozilla.org/security/advisories/mfsa2026-58/
Web page

Security Vulnerabilities fixed in Firefox 152 — Mozilla

https://www.mozilla.org/security/advisories/mfsa2026-57/
Web page

Access Denied

https://bugzilla.mozilla.org/show_bug.cgi?id=2023443

Vendor Advisories for CVE-2026-12289(20)

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

Patch Availability(21)

Vendor / EcosystemFix (by version range) / PatchReleasedSource
redhatthunderbird-0:140.12.0-1.el9_22026-07-15redhat
redhatthunderbird-0:140.12.0-1.el8_82026-07-14redhat
redhatthunderbird-0:140.12.0-1.el8_42026-07-14redhat
redhatthunderbird-0:140.12.0-1.el8_62026-07-14redhat
redhatthunderbird-0:140.12.0-1.el10_02026-07-13redhat
redhatthunderbird-0:140.12.0-1.el9_42026-07-13redhat
redhatfirefox-0:140.12.0-1.el9_42026-07-13redhat
redhatfirefox-0:140.12.0-1.el7_92026-07-13redhat
redhatthunderbird-0:140.12.0-1.el9_62026-07-13redhat
redhatfirefox-0:140.12.0-1.el9_62026-07-09redhat
redhatfirefox-0:140.12.0-1.el8_62026-07-09redhat
redhatfirefox-0:140.12.0-1.el9_22026-07-07redhat
redhatfirefox-0:140.12.0-1.el10_02026-07-07redhat
redhatfirefox-0:140.12.0-1.el8_82026-07-07redhat
redhatfirefox-0:140.12.0-1.el8_42026-07-07redhat
redhatthunderbird-0:140.12.0-1.el8_102026-06-30redhat
redhatthunderbird-0:140.12.0-1.el10_22026-06-29redhat
redhatthunderbird-0:140.12.0-1.el9_82026-06-25redhat
redhatfirefox-0:140.12.0-1.el10_22026-06-22redhat
redhatfirefox-0:140.12.0-1.el8_102026-06-22redhat
redhatfirefox-0:140.12.0-1.el9_82026-06-22redhat

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 (279 versions)
  • every version up to 140.12.0esr-1~deb11u1: fixed in 140.12.0esr-1~deb11u1
—
thunderbird1:102.0.1-1 ... 1:91.9.0-1~deb9u1 (330 versions)
  • every version up to 1:140.12.0esr-1~deb11u1: fixed in 1:140.12.0esr-1~deb11u1
—
Debian:12(2)
PackageVulnerable rangeFix by version rangeDependents
firefox-esr102.11.0esr-1 ... 140.9.1esr-1~deb13u1 (186 versions)
  • every version up to 140.12.0esr-1~deb12u1: fixed in 140.12.0esr-1~deb12u1
—
thunderbird1:102.11.0-1 ... 1:140.9.1esr-1~deb13u1 (215 versions)
  • every version up to 1:140.12.0esr-1~deb12u1: fixed in 1:140.12.0esr-1~deb12u1
—
Debian:13(2)
PackageVulnerable rangeFix by version rangeDependents
firefox-esr128.13.0esr-1 ... 140.9.1esr-1~deb13u1 (62 versions)
  • every version up to 140.12.0esr-1~deb13u1: fixed in 140.12.0esr-1~deb13u1
—
thunderbird1:128.13.0esr-1 ... 1:140.9.1esr-1~deb13u1 (71 versions)
  • every version up to 1:140.12.0esr-1~deb13u1: fixed in 1:140.12.0esr-1~deb13u1
—
Debian:14(2)
PackageVulnerable rangeFix by version rangeDependents
firefox-esr128.13.0esr-1 ... 140.9.1esr-1~deb13u1 (63 versions)
  • every version up to 140.12.0esr-1: fixed in 140.12.0esr-1
—
thunderbird1:128.13.0esr-1 ... 1:140.9.1esr-1~deb13u1 (72 versions)
  • every version up to 1:140.12.0esr-1: fixed in 1:140.12.0esr-1
—

Weakness Classification(2)

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

Additional Vendor Advisories

(1)

Vendors that published advisories for this CVE beyond the curated set above. Broader coverage but minimal per-row detail — click through for the original advisory.

Data Freshness Timeline

(refreshed 10× in last 7d / 25× 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 334 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 234 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-10-11 20:12 UTCEG score recompute
  2. 2026-10-11 18:24 UTCEG score recompute
  3. 2026-10-11 14:58 UTCEG score recompute
  4. 2026-10-11 13:48 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  5. 2026-10-10 19:59 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  6. 2026-10-09 20:06 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  7. 2026-10-08 17:11 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  8. 2026-10-07 23:47 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  9. 2026-10-06 15:17 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  10. 2026-10-05 17:42 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  11. 2026-10-04 23:21 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  12. 2026-10-03 14:25 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  13. 2026-10-01 19:49 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  14. 2026-09-30 15:02 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  15. 2026-09-29 15:20 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  16. 2026-09-26 15:58 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  17. 2026-09-23 13:47 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  18. 2026-09-20 20:15 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  19. 2026-09-18 19:27 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  20. 2026-09-16 05:14 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  21. 2026-09-14 03:33 UTCEG score recompute
  22. 2026-09-14 03:33 UTCVendor advisory
  23. 2026-09-14 03:33 UTCGHSA enrichmentGHSA-pp33-f8rg-g2pq · GitHub severity HIGH · GitHub CVSS 8.8
  24. 2026-09-13 16:46 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  25. 2026-09-12 15:00 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
Show 75 more
  1. 2026-09-11 14:52 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  2. 2026-09-11 09:36 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  3. 2026-09-10 09:34 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  4. 2026-09-08 22:00 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  5. 2026-09-07 16:01 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  6. 2026-09-06 13:47 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  7. 2026-09-04 05:06 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  8. 2026-09-02 14:11 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  9. 2026-09-01 13:53 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  10. 2026-09-01 04:39 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  11. 2026-08-30 22:50 UTCEG score recompute
  12. 2026-08-30 22:50 UTCVendor advisory
  13. 2026-08-30 22:50 UTCGHSA enrichmentGHSA-pp33-f8rg-g2pq · GitHub severity HIGH · GitHub CVSS 8.8
  14. 2026-08-30 19:17 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  15. 2026-08-30 01:21 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  16. 2026-08-28 21:40 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  17. 2026-08-27 14:24 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  18. 2026-08-25 13:48 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  19. 2026-08-24 23:26 UTCEG score recompute
  20. 2026-08-24 23:26 UTCVendor advisory
  21. 2026-08-24 23:26 UTCGHSA enrichmentGHSA-pp33-f8rg-g2pq · GitHub severity HIGH · GitHub CVSS 8.8
  22. 2026-08-23 21:56 UTCVendor advisory
  23. 2026-08-23 21:56 UTCGHSA enrichmentGHSA-pp33-f8rg-g2pq · GitHub severity HIGH · GitHub CVSS 8.8
  24. 2026-08-23 09:29 UTCEG score recompute
  25. 2026-08-23 09:29 UTCVendor advisory
  26. 2026-08-23 09:29 UTCGHSA enrichmentGHSA-pp33-f8rg-g2pq · GitHub severity HIGH · GitHub CVSS 8.8
  27. 2026-08-23 00:19 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  28. 2026-08-21 23:48 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  29. 2026-08-21 22:36 UTCVendor advisory
  30. 2026-08-21 22:36 UTCGHSA enrichmentGHSA-pp33-f8rg-g2pq · GitHub severity HIGH · GitHub CVSS 8.8
  31. 2026-08-21 09:46 UTCEG score recompute
  32. 2026-08-21 09:46 UTCVendor advisory
  33. 2026-08-21 09:46 UTCGHSA enrichmentGHSA-pp33-f8rg-g2pq · GitHub severity HIGH · GitHub CVSS 8.8
  34. 2026-08-20 22:55 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  35. 2026-08-20 21:05 UTCVendor advisory
  36. 2026-08-20 21:05 UTCGHSA enrichmentGHSA-pp33-f8rg-g2pq · GitHub severity HIGH · GitHub CVSS 8.8
  37. 2026-08-20 08:34 UTCEG score recompute
  38. 2026-08-20 08:34 UTCVendor advisory
  39. 2026-08-20 08:34 UTCGHSA enrichmentGHSA-pp33-f8rg-g2pq · GitHub severity HIGH · GitHub CVSS 8.8
  40. 2026-08-19 17:03 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  41. 2026-08-19 13:09 UTCEG score recompute
  42. 2026-08-19 13:09 UTCVendor advisory
  43. 2026-08-19 13:08 UTCGHSA enrichmentGHSA-pp33-f8rg-g2pq · GitHub severity HIGH · GitHub CVSS 8.8
  44. 2026-08-18 13:48 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  45. 2026-08-17 06:16 UTCVendor advisory
  46. 2026-08-17 06:16 UTCGHSA enrichmentGHSA-pp33-f8rg-g2pq · GitHub severity HIGH · GitHub CVSS 8.8
  47. 2026-08-16 16:54 UTCEG score recompute
  48. 2026-08-16 16:54 UTCVendor advisory
  49. 2026-08-16 16:54 UTCGHSA enrichmentGHSA-pp33-f8rg-g2pq · GitHub severity HIGH · GitHub CVSS 8.8
  50. 2026-08-16 14:56 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  51. 2026-08-16 04:27 UTCEG score recompute
  52. 2026-08-16 04:27 UTCVendor advisory
  53. 2026-08-16 04:27 UTCGHSA enrichmentGHSA-pp33-f8rg-g2pq · GitHub severity HIGH · GitHub CVSS 8.8
  54. 2026-08-16 02:14 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  55. 2026-08-15 16:01 UTCVendor advisory
  56. 2026-08-15 16:01 UTCGHSA enrichmentGHSA-pp33-f8rg-g2pq · GitHub severity HIGH · GitHub CVSS 8.8
  57. 2026-08-15 03:34 UTCEG score recompute
  58. 2026-08-15 03:34 UTCVendor advisory
  59. 2026-08-15 03:34 UTCGHSA enrichmentGHSA-pp33-f8rg-g2pq · GitHub severity HIGH · GitHub CVSS 8.8
  60. 2026-08-15 01:30 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  61. 2026-08-14 15:07 UTCVendor advisory
  62. 2026-08-14 15:07 UTCGHSA enrichmentGHSA-pp33-f8rg-g2pq · GitHub severity HIGH · GitHub CVSS 8.8
  63. 2026-08-14 02:40 UTCEG score recompute
  64. 2026-08-14 02:40 UTCVendor advisory
  65. 2026-08-14 02:40 UTCGHSA enrichmentGHSA-pp33-f8rg-g2pq · GitHub severity HIGH · GitHub CVSS 8.8
  66. 2026-08-13 22:00 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  67. 2026-08-13 14:14 UTCVendor advisory
  68. 2026-08-13 14:14 UTCGHSA enrichmentGHSA-pp33-f8rg-g2pq · GitHub severity HIGH · GitHub CVSS 8.8
  69. 2026-08-13 01:37 UTCEG score recompute
  70. 2026-08-13 01:37 UTCVendor advisory
  71. 2026-08-13 01:37 UTCGHSA enrichmentGHSA-pp33-f8rg-g2pq · GitHub severity HIGH · GitHub CVSS 8.8
  72. 2026-08-12 13:50 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  73. 2026-08-12 13:11 UTCVendor advisory
  74. 2026-08-12 13:11 UTCGHSA enrichmentGHSA-pp33-f8rg-g2pq · GitHub severity HIGH · GitHub CVSS 8.8
  75. 2026-08-12 00:44 UTCEG score recompute

Related CVEs(same vendor + same CWE)

Frequently asked(5)

What is CVE-2026-12289?
CVE-2026-12289 is a high-severity vulnerability; its CVE record was published on June 16, 2026. Privilege escalation in the Graphics: WebRender component. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Firefox ESR 115.37, Thunderbird 152, and Thunderbird 140.12.
When was the CVE record for CVE-2026-12289 published?
The CVE record for CVE-2026-12289 was published on June 16, 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-2026-12289 actively exploited?
CVE-2026-12289 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-2026-12289?
CVE-2026-12289 has a CVSS v3.1 base score of 8.8 (CISA-ADP / Vulnrichment enrichment; NVD's own analysis pending).
How do I remediate CVE-2026-12289?
A fix for CVE-2026-12289 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-12289 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-2026-12289

Explore →

Is Your Infrastructure Affected by CVE-2026-12289?

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

Book a Demo →Browse All CVEs