CVE-2016-3739

MEDIUMNVD 5.35.3—
EchelonGraph scoreMEDIUM confidence

Score 5.3 from GitHub Security Advisory published 2022-05-14. NVD baseline CVSS 5.3; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
5.3EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 7%CVSS: 5.3Exploit: None knownExposed: 0

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

The (1) mbed_connect_step1 function in lib/vtls/mbedtls.c and (2) polarssl_connect_step1 function in lib/vtls/polarssl.c in cURL and libcurl before 7.49.0, when using SSLv3 or making a TLS connection to a URL that uses a numerical IP address, allow remote attackers to spoof servers via an arbitrary valid certificate.

CVSS v3
5.3
EG Score
5.3(medium)
EG Risk
31(Track)
EG Risk 31/100SSVC: 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
Severity53% × 45%
Exploitation6% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
7%
EPSS %ILE
94%
KEV
Not listed

Published

May 20, 2016

Last Modified

June 17, 2026

References (22)

Affected Packages

(4 across 4 ecosystems)
Debian:11(1)
PackageVulnerable rangeFixed inDependents
curl—7.50.1-1—
Debian:12(1)
PackageVulnerable rangeFixed inDependents
curl—7.50.1-1—
Debian:13(1)
PackageVulnerable rangeFixed inDependents
curl—7.50.1-1—
Debian:14(1)
PackageVulnerable rangeFixed inDependents
curl—7.50.1-1—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 5× in last 7d / 18× 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 141 total refreshes for this CVE.

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

Related CVEs(same product + same CWE)

Frequently asked(5)

What is CVE-2016-3739?
CVE-2016-3739 is a medium vulnerability published on May 20, 2016. The (1) mbedconnectstep1 function in lib/vtls/mbedtls.c and (2) polarsslconnectstep1 function in lib/vtls/polarssl.c in cURL and libcurl before 7.49.0, when using SSLv3 or making a TLS connection to a URL that uses a numerical IP address, allow remote attackers to spoof servers via an arbitrary…
When was CVE-2016-3739 disclosed?
CVE-2016-3739 was first published in the National Vulnerability Database on May 20, 2016, with the most recent update on June 17, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2016-3739 actively exploited?
CVE-2016-3739 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 7% probability of exploitation in the next 30 days, which ranks it in the top 6.1% of all scored CVEs.
What is the CVSS score of CVE-2016-3739?
CVE-2016-3739 has a CVSS v3 base score of 5.3 (NVD).
How do I remediate CVE-2016-3739?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2016-3739, 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-2016-3739

Explore →

Is Your Infrastructure Affected by CVE-2016-3739?

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

Book a Demo →Browse All CVEs