CVE-2019-1691

MEDIUMNVD 5.85.8—
EchelonGraph scoreMEDIUM confidence

Score 5.8 from GitHub Security Advisory published 2022-05-13. NVD baseline CVSS 5.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
5.8EG
EchelonGraph verdictMonitorRemediate within your standard update timelines at low or medium mission impact and sooner than that at high (the SSVC decision on this page).
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 2.3%CVSS: 5.8Exploit: None knownExposed services: Not assessed

No fix has been recorded since the CVE record was published in 2019 — use a compensating control (WAF / firewall / segmentation) and check the vendor's advisory.

A vulnerability in the detection engine of Cisco Firepower Threat Defense Software could allow an unauthenticated, remote attacker to cause the unexpected restart of the SNORT detection engine, resulting in a denial of service (DoS) condition. The vulnerability is due to the incomplete error handling of the SSL or TLS packet header during the connection establishment. An attacker could exploit this vulnerability by sending a crafted SSL or TLS packet during the connection handshake. An exploit could allow the attacker to cause the SNORT detection engine to unexpectedly restart, resulting in a partial DoS condition while the detection engine restarts. Versions prior to 6.2.3.4 are affected.

CVSS v3
5.8
EG Score
5.8MEDIUMmedium confidence
EG Risk
42
EG Risk 42/100

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)
Severity58% × 45%
The EG Score, 5.8 of 10.
Exploitation2% × 40%
FIRST EPSS: the 30-day exploitation probability when EchelonGraph scored this CVE.
Automatability100% × 15%
CISA's SSVC Automatable value: yes (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at low or medium mission impact; Attend at high (mission-essential systems).
Exploitation none (CISA Vulnrichment) · Automatable yes (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: No fix has been recorded since the CVE record was published in 2019. Restrict network exposure of the affected system or apply the vendor's mitigation within your standard update timelines at low or medium mission impact and sooner than that at high, and check the vendor's advisory for a fix.
EPSS PROB
2.3%
EPSS %ILE
82nd
KEV
Not listed

SSVC (CISA's decision table, applied by EchelonGraph)Track at low or medium mission impact; Attend at high (mission-essential systems).

No fix has been recorded since the CVE record was published in 2019. Restrict network exposure of the affected system or apply the vendor's mitigation within your standard update timelines at low or medium mission impact and sooner than that at high, and check the vendor's advisory for a fix.

Exploitation none (CISA Vulnrichment) · Automatable yes (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

Published

February 21, 2019

Last Modified

August 11, 2026

Advisory Details (2)

Auto-updated Aug 12, 2026
No fix on record since 2019.
generic

Cisco Firepower Threat Defense Software SSL or TLS Denial of Service Vulnerability

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190220-fpwr-ssltls-dos
generic

SecurityFocus

http://www.securityfocus.com/bid/107099

Vendor Advisories for CVE-2019-1691(1)

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

Weakness Classification(2)

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

Data Freshness Timeline

(refreshed 7× 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 88 of 146 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. 12 repeat rows among the latest 100 are merged into the row they repeat. The 58 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-10-11 13:42 UTCEPSS rescoreEPSS 2.3% · 82nd percentile
  2. 2026-10-10 19:55 UTCEPSS rescoreEPSS 2.3% · 82nd percentile
  3. 2026-10-09 20:03 UTCEPSS rescoreEPSS 2.3% · 82nd percentile
  4. 2026-10-08 16:37 UTCEPSS rescoreEPSS 2.3% · 82nd percentile
  5. 2026-10-07 23:43 UTCEPSS rescoreEPSS 2.3% · 82nd percentile
  6. 2026-10-06 15:12 UTCEPSS rescoreEPSS 2.3% · 82nd percentile
  7. 2026-10-05 17:39 UTCEPSS rescoreEPSS 2.3% · 82nd percentile
  8. 2026-10-03 14:22 UTCEPSS rescoreEPSS 2.3% · 82nd percentile
  9. 2026-09-30 14:59 UTCEPSS rescoreEPSS 2.3% · 82nd percentile
  10. 2026-09-30 10:13 UTCEG score recompute
  11. 2026-09-28 13:46 UTCEPSS rescoreEPSS 2.3% · 82nd percentile
  12. 2026-09-27 13:40 UTCEPSS rescoreEPSS 2.3% · 82nd percentile
  13. 2026-09-26 15:54 UTCEPSS rescoreEPSS 2.3% · 82nd percentile
  14. 2026-09-26 00:20 UTCEPSS rescoreEPSS 2.3% · 82nd percentile
  15. 2026-09-24 13:59 UTCEPSS rescoreEPSS 2.3% · 82nd percentile
  16. 2026-09-23 13:43 UTCEPSS rescoreEPSS 2.3% · 82nd percentile
  17. 2026-09-22 14:43 UTCEPSS rescoreEPSS 2.3% · 82nd percentile
  18. 2026-09-21 20:28 UTCEPSS rescoreEPSS 2.3% · 82nd percentile
  19. 2026-09-20 20:10 UTCEPSS rescoreEPSS 2.3% · 82nd percentile
  20. 2026-09-18 19:22 UTCEPSS rescoreEPSS 2.3% · 82nd percentile
  21. 2026-09-17 19:22 UTCEPSS rescoreEPSS 2.3% · 82nd percentile
  22. 2026-09-16 14:04 UTCEPSS rescoreEPSS 2.3% · 82nd percentile
  23. 2026-09-15 03:05 UTCEPSS rescoreEPSS 2.3% · 82nd percentile
  24. 2026-09-13 16:42 UTCEPSS rescoreEPSS 2.3% · 82nd percentile
  25. 2026-09-12 14:56 UTCEPSS rescoreEPSS 2.3% · 82nd percentile
Show 63 more
  1. 2026-09-11 14:48 UTCEPSS rescoreEPSS 2.3% · 82nd percentile
  2. 2026-09-11 09:32 UTCEPSS rescoreEPSS 2.3% · 81st percentile
  3. 2026-09-07 15:57 UTCEPSS rescoreEPSS 2.3% · 81st percentile
  4. 2026-09-06 13:44 UTCEPSS rescoreEPSS 2.3% · 81st percentile
  5. 2026-09-05 15:24 UTCEPSS rescoreEPSS 2.3% · 81st percentile
  6. 2026-09-04 13:56 UTCEPSS rescoreEPSS 2.3% · 81st percentile
  7. 2026-09-02 14:07 UTCEPSS rescoreEPSS 2.3% · 81st percentile
  8. 2026-09-01 03:32 UTCEPSS rescoreEPSS 2.3% · 81st percentile
  9. 2026-08-30 19:13 UTCEPSS rescoreEPSS 2.3% · 81st percentile
  10. 2026-08-30 01:18 UTCEPSS rescoreEPSS 2.3% · 81st percentile
  11. 2026-08-28 21:36 UTCEPSS rescoreEPSS 2.3% · 81st percentile
  12. 2026-08-27 14:21 UTCEPSS rescoreEPSS 2.3% · 81st percentile
  13. 2026-08-26 14:42 UTCEPSS rescoreEPSS 2.3% · 81st percentile
  14. 2026-08-25 13:45 UTCEPSS rescoreEPSS 2.3% · 81st percentile
  15. 2026-08-24 14:11 UTCEPSS rescoreEPSS 2.3% · 81st percentile
  16. 2026-08-21 23:45 UTCEPSS rescoreEPSS 2.3% · 81st percentile
  17. 2026-08-20 22:51 UTCEPSS rescoreEPSS 2.3% · 81st percentile
  18. 2026-08-19 17:00 UTCEPSS rescoreEPSS 2.3% · 81st percentile
  19. 2026-08-18 13:44 UTCEPSS rescoreEPSS 2.3% · 81st percentile
  20. 2026-08-17 13:43 UTCEPSS rescoreEPSS 2.3% · 81st percentile
  21. 2026-08-16 14:52 UTCEPSS rescoreEPSS 2.3% · 81st percentile
  22. 2026-08-16 02:10 UTCEPSS rescoreEPSS 2.3% · 81st percentile
  23. 2026-08-15 01:26 UTCEPSS rescoreEPSS 2.3% · 81st percentile
  24. 2026-08-12 13:47 UTCEPSS rescoreEPSS 2.3% · 81st percentile
  25. 2026-08-11 20:00 UTCEG score recompute
  26. 2026-08-11 20:00 UTCGHSA enrichmentGHSA-95q2-c52x-vr4p · GitHub CVSS 5.8
  27. 2026-08-09 13:43 UTCEPSS rescoreEPSS 2.3% · 81st percentile
  28. 2026-08-08 16:33 UTCEPSS rescoreEPSS 2.3% · 81st percentile
  29. 2026-08-07 16:23 UTCEPSS rescoreEPSS 2.3% · 81st percentile
  30. 2026-08-06 13:43 UTCEPSS rescoreEPSS 2.3% · 81st percentile
  31. 2026-08-05 19:13 UTCEPSS rescoreEPSS 2.3% · 81st percentile
  32. 2026-08-04 15:05 UTCEPSS rescoreEPSS 2.3% · 81st percentile
  33. 2026-08-02 02:23 UTCEPSS rescoreEPSS 2.3% · 81st percentile
  34. 2026-08-01 04:12 UTCEPSS rescoreEPSS 2.3% · 81st percentile
  35. 2026-07-30 16:24 UTCEPSS rescoreEPSS 2.3% · 81st percentile
  36. 2026-07-30 01:27 UTCEPSS rescoreEPSS 2.3% · 81st percentile
  37. 2026-07-28 15:32 UTCEPSS rescoreEPSS 2.3% · 81st percentile
  38. 2026-07-26 14:51 UTCEPSS rescoreEPSS 2.3% · 81st percentile
  39. 2026-07-25 14:14 UTCEPSS rescoreEPSS 2.3% · 81st percentile
  40. 2026-07-24 14:14 UTCEPSS rescoreEPSS 2.3% · 81st percentile
  41. 2026-07-23 14:15 UTCEPSS rescoreEPSS 2.3% · 81st percentile
  42. 2026-07-23 01:41 UTCEG score recompute
  43. 2026-07-22 22:21 UTCEG score recompute
  44. 2026-07-22 14:05 UTCEPSS rescoreEPSS 2.3% · 81st percentile
  45. 2026-07-21 15:22 UTCEPSS rescoreEPSS 2.3% · 81st percentile
  46. 2026-07-20 17:04 UTCEPSS rescoreEPSS 2.3% · 81st percentile
  47. 2026-07-19 14:28 UTCEPSS rescoreEPSS 2.3% · 81st percentile
  48. 2026-07-19 02:26 UTCEPSS rescoreEPSS 2.3% · 81st percentile
  49. 2026-07-18 10:01 UTCEPSS rescoreEPSS 2.3% · 81st percentile
  50. 2026-07-16 16:59 UTCEPSS rescoreEPSS 2.3% · 81st percentile
  51. 2026-07-15 16:55 UTCEPSS rescoreEPSS 2.3% · 81st percentile
  52. 2026-07-13 22:27 UTCEPSS rescoreEPSS 2.3% · 80th percentile
  53. 2026-07-12 05:43 UTCEPSS rescoreEPSS 2.3% · 80th percentile
  54. 2026-07-11 08:24 UTCEPSS rescoreEPSS 2.3% · 80th percentile
  55. 2026-07-09 19:06 UTCEPSS rescoreEPSS 2.3% · 80th percentile
  56. 2026-07-08 15:11 UTCEPSS rescoreEPSS 2.3% · 80th percentile
  57. 2026-07-07 13:43 UTCEPSS rescoreEPSS 2.3% · 80th percentile
  58. 2026-07-06 16:25 UTCEPSS rescoreEPSS 2.3% · 80th percentile
  59. 2026-07-06 02:20 UTCEPSS rescoreEPSS 2.3% · 80th percentile
  60. 2026-07-05 02:27 UTCEPSS rescoreEPSS 2.3% · 80th percentile
  61. 2026-07-04 06:28 UTCEPSS rescoreEPSS 2.3% · 80th percentile
  62. 2026-07-01 15:03 UTCEPSS rescoreEPSS 2.3% · 80th percentile
  63. 2026-06-30 23:20 UTCEPSS rescoreEPSS 2.3% · 80th percentile

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2019-1691?
CVE-2019-1691 is a medium-severity vulnerability; its CVE record was published on February 21, 2019. A vulnerability in the detection engine of Cisco Firepower Threat Defense Software could allow an unauthenticated, remote attacker to cause the unexpected restart of the SNORT detection engine, resulting in a denial of service (DoS) condition. The vulnerability is due to the incomplete error…
When was CVE-2019-1691 made public?
CVE-2019-1691 was made public on February 20, 2019: that is the date its CVE record's CNA, Cisco Systems, Inc., gives for when the vulnerability was made public. The CVE record itself was published on February 21, 2019. EchelonGraph's copy of the record carries a last-modified date of August 11, 2026; the record at its source may have been updated since.
Is CVE-2019-1691 actively exploited?
CVE-2019-1691 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 2.3% probability of exploitation in the next 30 days (82nd percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2019-1691?
CVE-2019-1691 has a CVSS v3 base score of 5.8 (NVD).
How do I remediate CVE-2019-1691?
No fix for CVE-2019-1691 has been recorded since its CVE record was published in 2019. Restrict network exposure of the affected system or apply the vendor's mitigation — for example, keep it off the internet or limit it to trusted networks — and check the vendor's advisory for a fix. The vendor advisories EchelonGraph has for CVE-2019-1691 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

Explore the affected products and dependency analysis for CVE-2019-1691

Explore →

Is Your Infrastructure Affected by CVE-2019-1691?

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

Book a Demo →Browse All CVEs