CVE-2023-26964

HIGHNVD 7.57.5—
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 7.5 under NVD CVSS v3. EPSS exploit probability: 1.1%, top 37% 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
Elevated
7.5EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 1%CVSS: 7.5Exploit: Elevated riskExposed: 0

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

An issue was discovered in hyper v0.13.7. h2-0.2.4 Stream stacking occurs when the H2 component processes HTTP2 RST_STREAM frames. As a result, the memory and CPU usage are high which can lead to a Denial of Service (DoS).

CVSS v3
7.5
EG Score
7.5(medium)
EG Risk
65(Attend)
EG Risk 65/100SSVC: Attend

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
Severity75% × 45%
Exploitation40% × 40%
Automatability100% × 15%
Action: Remediate soon — notable exploitation risk.
EPSS PROB
1%
EPSS %ILE
64%
KEV
Not listed

Published

April 11, 2023

Last Modified

February 11, 2025

References (6)

Vendor Advisories for CVE-2023-26964(1)

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

Affected Packages

(4 across 4 ecosystems)
crates.io(1)
PackageVulnerable rangeFixed inDependents
h2—0.3.17—
Debian:12(1)
PackageVulnerable rangeFixed inDependents
rust-h2—0.3.13-2—
Debian:13(1)
PackageVulnerable rangeFixed inDependents
rust-h2—0.3.13-2—
Debian:14(1)
PackageVulnerable rangeFixed inDependents
rust-h2—0.3.13-2—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 7× in last 7d / 26× 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 158 total refreshes for this CVE.

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

Related CVEs(same vendor + same CWE)

Frequently asked(5)

What is CVE-2023-26964?
CVE-2023-26964 is a high vulnerability published on April 11, 2023. An issue was discovered in hyper v0.13.7. h2-0.2.4 Stream stacking occurs when the H2 component processes HTTP2 RST_STREAM frames. As a result, the memory and CPU usage are high which can lead to a Denial of Service (DoS).
When was CVE-2023-26964 disclosed?
CVE-2023-26964 was first published in the National Vulnerability Database on April 11, 2023, with the most recent update on February 11, 2025. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2023-26964 actively exploited?
CVE-2023-26964 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 1% probability of exploitation in the next 30 days, which ranks it in the top 36.0% of all scored CVEs.
What is the CVSS score of CVE-2023-26964?
CVE-2023-26964 has a CVSS v3 base score of 7.5 (NVD).
How do I remediate CVE-2023-26964?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2023-26964, 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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