CVE-2026-33870

HIGHPre-NVD 7.57.5
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 7.5 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.6%, top 52% 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, secondary
Trending — 3 sources updated this weekElevated
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

A fix is available — apply it.

Netty is an asynchronous, event-driven network application framework. In versions prior to 4.1.132.Final and 4.2.10.Final, Netty incorrectly parses quoted strings in HTTP/1.1 chunked transfer encoding extension values, enabling request smuggling attacks. Versions 4.1.132.Final and 4.2.10.Final fix the issue.

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
48%
KEV
Not listed

Published

March 27, 2026

Last Modified

August 4, 2026

Advisory Details (10)

Auto-updated Jul 1, 2026
⚠️ Active exploitation confirmed. Patch available. Sources: github, redhat.
generic

RFC 9110: HTTP Semantics | RFC Editor

https://www.rfc-editor.org/rfc/rfc9110
generic🔴 Active Exploitation

Funky chunks – addendum: a few more dirty tricks | w4ke.info

https://w4ke.info/2025/10/29/funky-chunks-2.html
generic🔴 Active Exploitation

Funky chunks: abusing ambiguous chunk line terminators for request smuggling | w4ke.info

https://w4ke.info/2025/06/18/funky-chunks.html
github Patch Available🟡 PoC Available

RFC violation: HTTP Request Smuggling primitive via Chunked Extension Quoted-String Parsing · Advisory · netty/netty · GitHub

https://github.com/netty/netty/security/advisories/GHSA-pwqr-wmgm-9rr8

Patch Availability(7)

Vendor / EcosystemFixed in / PatchReleasedSource
redhatnetty-codec-http2026-07-02redhat
redhatcryostat/jfr-datasource-rhel9:4.2.0-92026-05-26redhat
redhateap8-netty-transport-native-epoll-0:4.1.132-1.Final_redhat_00001.1.el9eap2026-05-18redhat
redhateap8-netty-transport-native-epoll-0:4.1.132-1.Final_redhat_00001.1.el8eap2026-05-18redhat
redhatpatch2026-05-04redhat
redhatdevspaces/server-rhel9:17767964452026-04-23redhat
redhatrhoai/odh-modelmesh-rhel9:17767568342026-04-23redhat

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.

Affected Packages

(5 across 5 ecosystems)
Debian:11(1)
PackageVulnerable rangeFixed inDependents
netty1:4.1.48-10 ... 1:4.1.48-9 (16 versions)
Debian:12(1)
PackageVulnerable rangeFixed inDependents
netty1:4.1.48-10 ... 1:4.1.48-9 (12 versions)
Debian:13(1)
PackageVulnerable rangeFixed inDependents
netty1:4.1.48-10 ... 1:4.1.48-16 (8 versions)
Debian:14(1)
PackageVulnerable rangeFixed inDependents
netty1:4.1.48-10 ... 1:4.1.48-16 (7 versions)
Maven(1)
PackageVulnerable rangeFixed inDependents
io.netty:netty-codec-http4.2.0.Alpha1 ... 4.2.9.Final (20 versions)4.2.10.Final

Weakness Classification(1)

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

Data Freshness Timeline

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

Frequently asked(5)

What is CVE-2026-33870?
CVE-2026-33870 is a high vulnerability published on March 27, 2026. Netty is an asynchronous, event-driven network application framework. In versions prior to 4.1.132.Final and 4.2.10.Final, Netty incorrectly parses quoted strings in HTTP/1.1 chunked transfer encoding extension values, enabling request smuggling attacks. Versions 4.1.132.Final and 4.2.10.Final fix…
When was CVE-2026-33870 disclosed?
CVE-2026-33870 was first published in the National Vulnerability Database on March 27, 2026, with the most recent update on August 4, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-33870 actively exploited?
CVE-2026-33870 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 52.0% of all scored CVEs.
What is the CVSS score of CVE-2026-33870?
CVE-2026-33870 has a CVSS v3 base score of 7.5 (NVD).
How do I remediate CVE-2026-33870?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-33870, 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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