CVE-2019-18224

CRITICALNVD 9.89.8—
EchelonGraph scoreMEDIUM confidence

Score 9.8 from GitHub Security Advisory (severity: CRITICAL) published 2022-05-24. NVD baseline CVSS 9.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
9.8EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 3.7%CVSS: 9.8Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

idn2_to_ascii_4i in lib/lookup.c in GNU libidn2 before 2.1.1 has a heap-based buffer overflow via a long domain string.

CVSS v3
9.8
EG Score
9.8CRITICALmedium confidence
EG Risk
50
EG Risk 50/100

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
Severity98% × 45%
Exploitation4% × 40%
Automatability30% × 15%
EPSS PROB
3.7%
EPSS %ILE
89th
KEV
Not listed

Published

October 21, 2019

Last Modified

November 21, 2024

Advisory Details (7)

Auto-updated Sep 27, 2026
Patch available. Sources: github_commit.
generic

GNU IDN Library 2: Multiple vulnerabilities (GLSA 202003-63) — Gentoo security

https://security.gentoo.org/glsa/202003-63
generic

Bugtraq: [SECURITY] [DSA 4613-1] libidn2 security update

https://seclists.org/bugtraq/2020/Feb/4
generic

[SECURITY] Fedora 30 Update: mingw-libidn2-2.2.0-1.fc30 - package-announce - Fedora mailing-lists

https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MINU5RKDFE6TKAFY5DRFN3WSFDS4DYVS/
generic

[SECURITY] Fedora 29 Update: mingw-libidn2-2.2.0-1.fc29 - package-announce - Fedora mailing-lists

https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/JDQVQ2XPV5BTZUFINT7AFJSKNNBVURNJ/
generic

Comparing libidn2-2.1.0...libidn2-2.1.1 · libidn/libidn2 · GitHub

https://github.com/libidn/libidn2/compare/libidn2-2.1.0...libidn2-2.1.1
github_commit

commit e4d1558aa2c1 (libidn/libidn2)

Fix landed in libidn/libidn2 commit e4d1558aa2c1 — awaiting tagged release

https://github.com/libidn/libidn2/commit/e4d1558aa2c1c04a05066ee8600f37603890ba8c
generic
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=12420

Patch Availability(2)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntulibidn2-doc (2.0.5-1ubuntu0.3) @ disco2026-05-27ubuntu
redhatlibidn2-0:2.2.0-1.el82019-11-05redhat

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

(18 across 18 ecosystems)
Alpine:v3.12(1)
PackageVulnerable rangeFixed inDependents
libidn2—2.1.1-r0—
Alpine:v3.13(1)
PackageVulnerable rangeFixed inDependents
libidn2—2.1.1-r0—
Alpine:v3.14(1)
PackageVulnerable rangeFixed inDependents
libidn2—2.1.1-r0—
Alpine:v3.15(1)
PackageVulnerable rangeFixed inDependents
libidn2—2.1.1-r0—
Alpine:v3.16(1)
PackageVulnerable rangeFixed inDependents
libidn2—2.1.1-r0—
Alpine:v3.17(1)
PackageVulnerable rangeFixed inDependents
libidn2—2.1.1-r0—
Alpine:v3.18(1)
PackageVulnerable rangeFixed inDependents
libidn2—2.1.1-r0—
Alpine:v3.19(1)
PackageVulnerable rangeFixed inDependents
libidn2—2.1.1-r0—
Alpine:v3.20(1)
PackageVulnerable rangeFixed inDependents
libidn2—2.1.1-r0—
Alpine:v3.21(1)
PackageVulnerable rangeFixed inDependents
libidn2—2.1.1-r0—
Alpine:v3.22(1)
PackageVulnerable rangeFixed inDependents
libidn2—2.1.1-r0—
Alpine:v3.23(1)
PackageVulnerable rangeFixed inDependents
libidn2—2.1.1-r0—
Alpine:v3.24(1)
PackageVulnerable rangeFixed inDependents
libidn2—2.1.1-r0—
Debian:10(1)
PackageVulnerable rangeFixed inDependents
libidn22.0.5-12.0.5-1+deb10u1—
Debian:11(1)
PackageVulnerable rangeFixed inDependents
libidn2—2.2.0-1—
Debian:12(1)
PackageVulnerable rangeFixed inDependents
libidn2—2.2.0-1—
Debian:13(1)
PackageVulnerable rangeFixed inDependents
libidn2—2.2.0-1—
Debian:14(1)
PackageVulnerable rangeFixed inDependents
libidn2—2.2.0-1—

Weakness Classification(1)

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

All Vendor Advisories

(2)

Every vendor that published an advisory referencing this CVE — pulled from our cve_vendor_advisories aggregation. Click any row for the vendor's original advisory page.

Data Freshness Timeline

(refreshed 9× in last 7d / 25× 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 152 total refreshes for this CVE.

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

Related CVEs(same product + same vendor + same CWE)

Same product

1 shown

Alpine:v3.12:libidn2

Same vendor

1 shown

ubuntu:USN-4168-1

Frequently asked(5)

What is CVE-2019-18224?
CVE-2019-18224 is a critical vulnerability published on October 21, 2019. idn2toascii_4i in lib/lookup.c in GNU libidn2 before 2.1.1 has a heap-based buffer overflow via a long domain string.
When was CVE-2019-18224 disclosed?
CVE-2019-18224 was first published on October 21, 2019, with the most recent update on November 21, 2024. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2019-18224 actively exploited?
CVE-2019-18224 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 3.7% probability of exploitation in the next 30 days (89th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2019-18224?
CVE-2019-18224 has a CVSS v3 base score of 9.8 (NVD).
How do I remediate CVE-2019-18224?
A fix for CVE-2019-18224 is available: update to the fixed version the vendor names in its advisory.

Dependency Blast Radius

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