CVE-2020-11100

HIGHNVD 8.88.8—
EchelonGraph scoreMEDIUM confidence

Score 8.8 from GitHub Security Advisory published 2022-05-24. NVD baseline CVSS 8.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
Trending — 3 sources updated this weekElevated
8.8
EchelonGraph verdictPatch this weekExploitation is likely or a public exploit exists.
  • High exploitation likelihood — EPSS 61%
CISA-KEV: Not listedEPSS: 61%CVSS: 8.8Exploit: NoneExposed: 0

A fix is available — apply it.

In hpack_dht_insert in hpack-tbl.c in the HPACK decoder in HAProxy 1.8 through 2.x before 2.1.4, a remote attacker can write arbitrary bytes around a certain location on the heap via a crafted HTTP/2 request, possibly causing remote code execution.

CVSS v3
8.8
EG Score
8.8(medium)
EG Risk
—
EPSS
99.1%
KEV
Not listed

Published

April 2, 2020

Last Modified

November 21, 2024

References (28)

Vendor Advisories for CVE-2020-11100(5)

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

Patch Availability(6)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntuvim-haproxy (2.0.5-1ubuntu0.4) @ eoan2026-05-27ubuntu
redhathaproxy-0:2.0.13-3.el72020-05-04redhat
redhathaproxy-0:1.8.23-3.el72020-04-07redhat
redhathaproxy-0:1.8.15-6.el8_1.12020-04-02redhat
redhathaproxy-0:1.8.15-5.el8_0.12020-04-02redhat
redhatrh-haproxy18-haproxy-0:1.8.17-1.el7.12020-04-02redhat

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.

Weakness Classification(1)

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

Additional Vendor Advisories

(1)

Vendors that published advisories for this CVE beyond the curated set above. Broader coverage but minimal per-row detail — click through for the original advisory.

Data Freshness Timeline

(refreshed 11× in last 7d / 33× 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. 2026-07-22 22:32 UTCEG score recompute
  2. 2026-07-22 14:05 UTCEPSS rescore
  3. 2026-07-21 15:22 UTCEPSS rescore
  4. 2026-07-21 15:22 UTCEPSS rescore
  5. 2026-07-20 17:04 UTCEPSS rescore
  6. 2026-07-19 14:59 UTCOSV refresh
  7. 2026-07-19 14:28 UTCEPSS rescore
  8. 2026-07-19 14:28 UTCEPSS rescore
  9. 2026-07-18 10:02 UTCEPSS rescore
  10. 2026-07-16 16:59 UTCEPSS rescore
  11. 2026-07-16 16:59 UTCEPSS rescore
  12. 2026-07-15 16:55 UTCEPSS rescore
  13. 2026-07-13 22:27 UTCEPSS rescore
  14. 2026-07-13 06:10 UTCEPSS rescore
  15. 2026-07-13 06:10 UTCEPSS rescore
  16. 2026-07-12 05:44 UTCEPSS rescore
  17. 2026-07-11 08:24 UTCEPSS rescore
  18. 2026-07-09 19:06 UTCEPSS rescore
  19. 2026-07-06 16:25 UTCEPSS rescore
  20. 2026-07-06 16:25 UTCEPSS rescore
  21. 2026-07-05 02:27 UTCEPSS rescore
  22. 2026-07-02 02:47 UTCOSV refresh
  23. 2026-07-01 15:03 UTCEPSS rescore
  24. 2026-07-01 15:03 UTCEPSS rescore
  25. 2026-06-30 23:20 UTCEPSS rescore
Show 52 more
  1. 2026-06-30 23:20 UTCEPSS rescore
  2. 2026-06-28 04:54 UTCEPSS rescore
  3. 2026-06-28 04:54 UTCEPSS rescore
  4. 2026-06-27 03:06 UTCEPSS rescore
  5. 2026-06-25 13:47 UTCEPSS rescore
  6. 2026-06-25 13:47 UTCEPSS rescore
  7. 2026-06-23 21:31 UTCEPSS rescore
  8. 2026-06-23 21:31 UTCEPSS rescore
  9. 2026-06-22 14:23 UTCEPSS rescore
  10. 2026-06-22 14:23 UTCEPSS rescore
  11. 2026-06-21 01:57 UTCEPSS rescore
  12. 2026-06-21 01:57 UTCEPSS rescore
  13. 2026-06-18 17:50 UTCEPSS rescore
  14. 2026-06-18 17:50 UTCEPSS rescore
  15. 2026-06-17 17:50 UTCEPSS rescore
  16. 2026-06-17 17:50 UTCEPSS rescore
  17. 2026-06-16 17:50 UTCEPSS rescore
  18. 2026-06-16 17:50 UTCEPSS rescore
  19. 2026-06-15 17:46 UTCEPSS rescore
  20. 2026-06-14 05:43 UTCOSV refresh
  21. 2026-06-13 22:58 UTCEPSS rescore
  22. 2026-06-13 22:58 UTCEPSS rescore
  23. 2026-06-12 23:09 UTCEPSS rescore
  24. 2026-06-11 13:58 UTCEPSS rescore
  25. 2026-06-10 22:16 UTCEPSS rescore
  26. 2026-06-10 22:16 UTCEPSS rescore
  27. 2026-06-10 13:20 UTCEPSS rescore
  28. 2026-06-08 14:15 UTCEPSS rescore
  29. 2026-06-08 14:15 UTCEPSS rescore
  30. 2026-06-07 15:23 UTCEPSS rescore
  31. 2026-06-07 15:23 UTCEPSS rescore
  32. 2026-06-05 22:45 UTCEPSS rescore
  33. 2026-06-05 22:45 UTCEPSS rescore
  34. 2026-06-05 06:08 UTCEPSS rescore
  35. 2026-06-02 20:11 UTCEPSS rescore
  36. 2026-06-02 20:11 UTCEPSS rescore
  37. 2026-06-01 13:50 UTCEPSS rescore
  38. 2026-05-31 22:29 UTCEPSS rescore
  39. 2026-05-31 22:29 UTCEPSS rescore
  40. 2026-05-31 00:15 UTCEPSS rescore
  41. 2026-05-31 00:14 UTCEPSS rescore
  42. 2026-05-29 13:42 UTCEPSS rescore
  43. 2026-05-29 13:42 UTCEPSS rescore
  44. 2026-05-28 13:43 UTCEPSS rescore
  45. 2026-05-28 13:43 UTCEPSS rescore
  46. 2026-05-27 13:39 UTCEPSS rescore
  47. 2026-05-27 05:39 UTCEG score recompute
  48. 2026-05-27 05:39 UTCVendor advisory
  49. 2026-05-27 05:39 UTCGHSA enrichment
  50. 2026-05-26 07:17 UTCEPSS rescore
  51. 2026-05-26 07:17 UTCEPSS rescore
  52. 2026-05-24 16:21 UTCOSV refresh

Related CVEs(same vendor + same CWE)

Frequently asked(5)

What is CVE-2020-11100?
CVE-2020-11100 is a high vulnerability published on April 2, 2020. In hpackdhtinsert in hpack-tbl.c in the HPACK decoder in HAProxy 1.8 through 2.x before 2.1.4, a remote attacker can write arbitrary bytes around a certain location on the heap via a crafted HTTP/2 request, possibly causing remote code execution.
When was CVE-2020-11100 disclosed?
CVE-2020-11100 was first published in the National Vulnerability Database on April 2, 2020, 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-2020-11100 actively exploited?
CVE-2020-11100 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 99.1% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2020-11100?
CVE-2020-11100 has a CVSS v3 base score of 8.8 (NVD).
How do I remediate CVE-2020-11100?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2020-11100, 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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