CVE-2013-4421

NONECVSS 0.0
0.0
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • No confirmed exploitation signals yet
CISA-KEV: Not listedEPSS: 6%CVSS: —Exploit: NoneExposed: 0

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

The buf_decompress function in packet.c in Dropbear SSH Server before 2013.59 allows remote attackers to cause a denial of service (memory consumption) via a compressed packet that has a large size when it is decompressed.

CVSS v3
—
EG Score
0.0(none)
EPSS
92.9%
KEV
Not listed

Published

October 25, 2013

Last Modified

April 29, 2026

References (20)

Data Freshness Timeline

(refreshed 8× in last 7d / 35× 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.

  1. 2026-07-06 02:19 UTCEPSS rescore
  2. 2026-07-06 02:19 UTCEPSS rescore
  3. 2026-07-05 05:21 UTCOSV refresh
  4. 2026-07-05 02:26 UTCEPSS rescore
  5. 2026-07-04 06:27 UTCEPSS rescore
  6. 2026-07-01 15:02 UTCEPSS rescore
  7. 2026-06-30 23:19 UTCEPSS rescore
  8. 2026-06-30 23:19 UTCEPSS rescore
  9. 2026-06-29 14:02 UTCEPSS rescore
  10. 2026-06-28 14:03 UTCEPSS rescore
  11. 2026-06-28 04:53 UTCEPSS rescore
  12. 2026-06-28 04:53 UTCEPSS rescore
  13. 2026-06-27 03:05 UTCEPSS rescore
  14. 2026-06-25 13:46 UTCEPSS rescore
  15. 2026-06-24 14:02 UTCEPSS rescore
  16. 2026-06-24 14:02 UTCEPSS rescore
  17. 2026-06-23 21:30 UTCEPSS rescore
  18. 2026-06-22 14:22 UTCEPSS rescore
  19. 2026-06-22 14:22 UTCEPSS rescore
  20. 2026-06-21 14:53 UTCEPSS rescore
  21. 2026-06-19 19:23 UTCEPSS rescore
  22. 2026-06-19 19:22 UTCEPSS rescore
  23. 2026-06-18 17:49 UTCEPSS rescore
  24. 2026-06-18 17:49 UTCEPSS rescore
  25. 2026-06-17 17:49 UTCEPSS rescore
Show 46 more
  1. 2026-06-17 17:49 UTCEPSS rescore
  2. 2026-06-16 17:49 UTCEPSS rescore
  3. 2026-06-16 17:49 UTCEPSS rescore
  4. 2026-06-16 16:39 UTCOSV refresh
  5. 2026-06-15 17:44 UTCEPSS rescore
  6. 2026-06-14 23:14 UTCEPSS rescore
  7. 2026-06-12 23:08 UTCEPSS rescore
  8. 2026-06-11 13:56 UTCEPSS rescore
  9. 2026-06-10 13:18 UTCEPSS rescore
  10. 2026-06-08 14:14 UTCEPSS rescore
  11. 2026-06-07 15:22 UTCEPSS rescore
  12. 2026-06-06 13:45 UTCEPSS rescore
  13. 2026-06-06 13:45 UTCEPSS rescore
  14. 2026-06-05 22:44 UTCEPSS rescore
  15. 2026-06-05 22:44 UTCEPSS rescore
  16. 2026-06-05 06:08 UTCEPSS rescore
  17. 2026-06-05 06:08 UTCEPSS rescore
  18. 2026-06-02 20:10 UTCEPSS rescore
  19. 2026-06-02 20:10 UTCEPSS rescore
  20. 2026-06-01 13:49 UTCEPSS rescore
  21. 2026-06-01 13:49 UTCEPSS rescore
  22. 2026-05-31 22:28 UTCEPSS rescore
  23. 2026-05-31 22:28 UTCEPSS rescore
  24. 2026-05-29 13:41 UTCEPSS rescore
  25. 2026-05-29 13:41 UTCEPSS rescore
  26. 2026-05-28 21:50 UTCEG score recompute
  27. 2026-05-28 21:50 UTCGHSA enrichment
  28. 2026-05-28 13:42 UTCEPSS rescore
  29. 2026-05-28 13:42 UTCEPSS rescore
  30. 2026-05-28 13:42 UTCEPSS rescore
  31. 2026-05-27 13:38 UTCEPSS rescore
  32. 2026-05-27 13:38 UTCEPSS rescore
  33. 2026-05-26 07:16 UTCEPSS rescore
  34. 2026-05-26 07:16 UTCEPSS rescore
  35. 2026-05-24 16:43 UTCEPSS rescore
  36. 2026-05-24 09:21 UTCOSV refresh
  37. 2026-05-22 21:15 UTCEPSS rescore
  38. 2026-05-22 21:15 UTCEPSS rescore
  39. 2026-05-22 21:15 UTCEPSS rescore
  40. 2026-05-20 22:37 UTCEPSS rescore
  41. 2026-05-20 22:37 UTCEPSS rescore
  42. 2026-05-20 11:21 UTCEPSS rescore
  43. 2026-05-20 11:21 UTCEPSS rescore
  44. 2026-05-20 11:21 UTCEPSS rescore
  45. 2026-05-18 21:29 UTCEPSS rescore
  46. 2026-05-18 21:29 UTCEPSS rescore

Frequently asked(4)

What is CVE-2013-4421?
CVE-2013-4421 is a none vulnerability published on October 25, 2013. The buf_decompress function in packet.c in Dropbear SSH Server before 2013.59 allows remote attackers to cause a denial of service (memory consumption) via a compressed packet that has a large size when it is decompressed.
When was CVE-2013-4421 disclosed?
CVE-2013-4421 was first published in the National Vulnerability Database on October 25, 2013, with the most recent update on April 29, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2013-4421 actively exploited?
CVE-2013-4421 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 92.9% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
How do I remediate CVE-2013-4421?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2013-4421, 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

Explore the affected products and dependency analysis for CVE-2013-4421

Explore →

Is Your Infrastructure Affected by CVE-2013-4421?

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

Start Free Scan →Browse All CVEs