CVE-2019-19977

CRITICALNVD 9.89.8—
EchelonGraph scoreMEDIUM confidence

This critical-severity CVE scores 9.8 under NVD CVSS v3. EPSS exploit probability: 3.1%, top 14% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, 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%CVSS: 9.8Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

libESMTP through 1.0.6 mishandles domain copying into a fixed-size buffer in ntlm_build_type_2 in ntlm/ntlmstruct.c, as demonstrated by a stack-based buffer over-read.

CVSS v3
9.8
EG Score
9.8(medium)
EG Risk
50(Track)
EG Risk 50/100SSVC: 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
Severity98% × 45%
Exploitation3% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
3%
EPSS %ILE
87%
KEV
Not listed

Published

December 26, 2019

Last Modified

November 21, 2024

Advisory Details (2)

Auto-updated Sep 20, 2026
No patch confirmed yet.
generic

libESMTP - A Library for Posting Electronic Mail

https://web.archive.org/web/20190528215510/http://brianstafford.info/libesmtp/
generic

libesmtp/ntlm/ntlmstruct.c at ca5bd0800ef1da234315da4c59716568eb5e6402 · jbouse-debian/libesmtp · GitHub

https://github.com/jbouse-debian/libesmtp/blob/ca5bd0800ef1da234315da4c59716568eb5e6402/ntlm/ntlmstruct.c#L228-L242

Affected Packages

(4 across 4 ecosystems)
Debian:11(1)
PackageVulnerable rangeFixed inDependents
libesmtp1.0.6-4.3 ... 1.1.0-3.2 (7 versions)——
Debian:12(1)
PackageVulnerable rangeFixed inDependents
libesmtp1.1.0-3, 1.1.0-3.1, 1.1.0-3.1~deb12u1, 1.1.0-3.2——
Debian:13(1)
PackageVulnerable rangeFixed inDependents
libesmtp1.1.0-3.2——
Debian:14(1)
PackageVulnerable rangeFixed inDependents
libesmtp1.1.0-3.2——

Weakness Classification(1)

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

All Vendor Advisories

(1)

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 6× 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 148 total refreshes for this CVE.

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

Related CVEs

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Frequently asked(5)

What is CVE-2019-19977?
CVE-2019-19977 is a critical vulnerability published on December 26, 2019. libESMTP through 1.0.6 mishandles domain copying into a fixed-size buffer in ntlmbuildtype_2 in ntlm/ntlmstruct.c, as demonstrated by a stack-based buffer over-read.
When was CVE-2019-19977 disclosed?
CVE-2019-19977 was first published in the National Vulnerability Database on December 26, 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-2019-19977 actively exploited?
CVE-2019-19977 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 3% probability of exploitation in the next 30 days, which ranks it in the top 13.5% of all scored CVEs.
What is the CVSS score of CVE-2019-19977?
CVE-2019-19977 has a CVSS v3 base score of 9.8 (NVD).
How do I remediate CVE-2019-19977?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2019-19977, 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

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