CVE-2026-16391

HIGHPre-NVD 7.57.5—
EchelonGraph scoreMEDIUM confidence

Score 7.5 from GitHub Security Advisory (severity: HIGH) published 2026-07-21. CISA-ADP (Vulnrichment) CVSS v3.1 baseline 7.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: cisa-adp, epss, ghsa
Trending — 4 sources updated this week
7.5EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 7.5Exploit: None knownExposed: 0

A fix is available — apply it.

Information disclosure in the Storage: IndexedDB component. This vulnerability was fixed in Firefox 153, Firefox ESR 140.13, Thunderbird 153, and Thunderbird 140.13.

CVSS v3
7.5
EG Score
7.5(medium)
EG Risk
49(Track)
EG Risk 49/100SSVC: Track

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
Severity75% × 45%
Exploitation0% × 40%
Automatability100% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
25%
KEV
Not listed

Published

July 21, 2026

Last Modified

July 24, 2026

Advisory Details (3)

Auto-updated Jul 22, 2026
⚠️ Active exploitation confirmed. No patch confirmed yet.
generic🔴 Active Exploitation

Security Vulnerabilities fixed in Firefox ESR 140.13 — Mozilla

https://www.mozilla.org/security/advisories/mfsa2026-70/
generic

Security Vulnerabilities fixed in Firefox 153 — Mozilla

https://www.mozilla.org/security/advisories/mfsa2026-68/
generic

Access Denied

https://bugzilla.mozilla.org/show_bug.cgi?id=2044536

Vendor Advisories for CVE-2026-16391(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 / EcosystemFixed in / PatchReleasedSource
redhatfirefox-0:140.13.0-1.el8_82026-08-12redhat
redhatfirefox-0:140.13.0-1.el9_62026-08-12redhat
redhatfirefox-0:140.13.0-1.el8_42026-08-12redhat
redhatfirefox-0:140.13.0-1.el9_22026-08-12redhat
redhatfirefox-0:140.13.0-1.el9_42026-08-12redhat
redhatfirefox-0:140.13.0-1.el10_02026-08-12redhat
redhatfirefox-0:140.13.0-1.el7_92026-08-12redhat
redhatfirefox-0:140.13.0-1.el8_62026-08-12redhat
redhatthunderbird-0:140.13.0-1.el9_22026-08-11redhat
redhatthunderbird-0:140.13.0-1.el9_42026-08-11redhat
redhatthunderbird-0:140.13.0-1.el9_62026-08-11redhat
redhatthunderbird-0:140.13.0-1.el10_02026-08-11redhat
redhatthunderbird-0:140.13.0-1.el8_42026-08-11redhat
redhatthunderbird-0:140.13.0-1.el8_62026-08-11redhat
redhatthunderbird-0:140.13.0-1.el8_82026-08-11redhat
redhatthunderbird-0:140.13.0-1.el9_82026-08-04redhat
redhatthunderbird-0:140.13.0-1.el8_102026-08-04redhat
redhatthunderbird-0:140.13.0-1.el10_22026-08-03redhat
redhatfirefox-0:140.13.0-1.el9_82026-08-03redhat
redhatfirefox-0:140.13.0-1.el8_102026-07-28redhat
redhatfirefox-0:140.13.0-1.el10_22026-07-28redhat

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 rangeFixed inDependents
firefox-esr102.1.0esr-1 ... 91.9.1esr-1~deb9u1 (283 versions)140.13.0esr-1~deb11u1—
thunderbird1:102.0.1-1 ... 1:91.9.0-1~deb9u1 (334 versions)1:140.13.0esr-1—
Debian:12(2)
PackageVulnerable rangeFixed inDependents
firefox-esr102.11.0esr-1 ... 140.9.1esr-1~deb13u1 (190 versions)140.13.0esr-1~deb12u1—
thunderbird1:102.11.0-1 ... 1:140.9.1esr-1~deb13u1 (220 versions)1:140.13.0esr-2~deb12u1—
Debian:13(2)
PackageVulnerable rangeFixed inDependents
firefox-esr128.13.0esr-1 ... 140.9.1esr-1~deb13u1 (66 versions)140.13.0esr-1~deb13u1—
thunderbird1:128.13.0esr-1 ... 1:140.9.1esr-1~deb13u1 (76 versions)1:140.13.0esr-2~deb13u1—
Debian:14(2)
PackageVulnerable rangeFixed inDependents
firefox-esr128.13.0esr-1 ... 140.9.1esr-1~deb13u1 (67 versions)140.13.0esr-1—
thunderbird1:128.13.0esr-1 ... 1:140.9.1esr-1~deb13u1 (73 versions)1:140.13.0esr-1—

Weakness Classification(1)

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 25× in last 7d / 113× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. 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. Most recent first.

Showing the most recent 100 of 269 total refreshes for this CVE.

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

Frequently asked(5)

What is CVE-2026-16391?
CVE-2026-16391 is a high vulnerability published on July 21, 2026. Information disclosure in the Storage: IndexedDB component. This vulnerability was fixed in Firefox 153, Firefox ESR 140.13, Thunderbird 153, and Thunderbird 140.13.
When was CVE-2026-16391 disclosed?
CVE-2026-16391 was first published in the National Vulnerability Database on July 21, 2026, with the most recent update on July 24, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-16391 actively exploited?
CVE-2026-16391 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 74.5% of all scored CVEs.
What is the CVSS score of CVE-2026-16391?
CVE-2026-16391 has a CVSS v3.1 base score of 7.5 (CISA-ADP / Vulnrichment enrichment; NVD's own analysis pending).
How do I remediate CVE-2026-16391?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-16391, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-16391

Explore →

Is Your Infrastructure Affected by CVE-2026-16391?

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

Start Free Scan →Browse All CVEs