CVE-2026-59899

HIGHNVD 7.57.5
EchelonGraph scoreMEDIUM confidence

“—” beside the score: it is equal to NVD's CVSS score.

This high-severity CVE scores 7.5 under NVD CVSS v3. EPSS exploit probability: 0.6% (48th percentile of EPSS-scored CVEs). No GitHub Security Advisory CVSS is on record for this CVE.

Triggered by: Headline CVSS from NVD CVSS v3
Sources: EPSS, NVD CVSS v3
Trending — 3 sources updated this week

Also known asEUVD-2026-50443 (ENISA EUVD) · GHSA-q4f6-jm68-57ww (GitHub Security Advisories)Source: ENISA EUVD

7.5EG
EchelonGraph verdictPlan a fixRemediate within your standard update timelines at low or medium mission impact and sooner than that at high (the SSVC decision on this page).
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0.6%CVSS: 7.5Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

Netty is an asynchronous, event-driven network application framework. Prior to versions 4.1.136.Final and 4.2.16.Final, HttpContentEncoder (the superclass of the production handler HttpContentCompressor) maintains a per-channel ArrayDeque named acceptEncodingQueue that accumulates attacker-controlled data without any size limit. The queue is filled on the I/O thread for every inbound HTTP request and drained only when the application later writes a non-1xx response. This creates a resource exhaustion vulnerability when an attacker exploits HTTP/1.1 pipelining to flood the connection with requests faster than the application produces responses. This issue has been fixed in versions 4.1.136.Final and 4.2.16.Final.

CVSS v3
7.5
EG Score
7.5HIGHmedium confidence
EG Risk
49
EG Risk 49/100

EG Risk is EchelonGraph's 0–100 priority score. It fuses impact severity (EG Severity, the CVSS base score, never the KEV-floored or EPSS-lifted EG Score) with real-world exploitation and automatability, under weights EchelonGraph set by hand, so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner.

How it’s computed (value × EchelonGraph’s weight)
Severity75% × 45%
Impact severity (EG Severity): CVSS 7.5 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation0.6% × 40%
FIRST EPSS: the 30-day exploitation probability when EchelonGraph scored this CVE.
Automatability100% × 15%
CISA's SSVC Automatable value: yes (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at low or medium mission impact; Attend at high (mission-essential systems).
Exploitation none (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE.
Action: A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.
EPSS PROB
0.6%
EPSS %ILE
48th
KEV
Not listed

What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)

The EG score (7.5): severity, escalated by confirmed exploitation. This CVE's 7.5 is its impact severity (EG Severity), not escalated.

EG Severity
7.5 HIGHCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.NVD CVSS v3 · CVSS v3.0 or v3.1
EG Likelihood
0.6% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-24). FIRST's exploitation probability, not an EchelonGraph model.
Confirmed exploitation
None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
EG Priority
SSVC Track at medium mission impactTrack at low or medium mission impact; Attend at high (mission-essential systems).CISA BOD 26-04: 14 days if the affected system is publicly exposed; 60 days if it is not.Each input and its source: the SSVC and BOD 26-04 blocks below.

SSVC (CISA's decision table, applied by EchelonGraph)Track at low or medium mission impact; Attend at high (mission-essential systems).

A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.

Exploitation none (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table

BOD 26-04 (CISA's remediation timeline, Table 1)14 days if the affected system is publicly exposed; 60 days if it is not.

In CISA KEV no (CISA's KEV catalog) · Automatable yes (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it

Published

July 22, 2026

Last Modified

August 6, 2026

Advisory Details (3)

Auto-updated Jul 29, 2026
Patch available. Sources: github, github_release.
GitHub release Patch Available

netty-4.2.16.Final

Patch available: netty/netty netty-4.2.16.Final

https://github.com/netty/netty/releases/tag/netty-4.2.16.Final
GitHub release Patch Available

netty-4.1.136.Final

Patch available: netty/netty netty-4.1.136.Final

https://github.com/netty/netty/releases/tag/netty-4.1.136.Final
GitHub advisoryMentions a patch (unverified)

[HttpContentEncoder] Unbounded Per-Connection Queue Growth via HTTP/1.1 Pipelining Leads to Denial of Service · Advisory · netty/netty · GitHub

https://github.com/netty/netty/security/advisories/GHSA-q4f6-jm68-57ww

Patch Availability(10)

Vendor / EcosystemFix (by version range) / PatchReleasedSource
redhatrhoai/odh-trustyai-service-rhel9:17917925252026-10-19redhat
redhatnetty-codec-http2026-10-06redhat
redhateap8-xml-security-0:3.0.6-1.redhat_00001.1.el9eap2026-09-22redhat
redhateap8-xml-security-0:3.0.6-1.redhat_00001.1.el8eap2026-09-22redhat
redhateap8-xml-security-0:3.0.6-1.redhat_00001.1.el10eap2026-09-22redhat
redhatdevspaces/server-rhel9:17891637982026-09-17redhat
redhatcryostat/jfr-datasource-rhel9:4.2.0-142026-09-16redhat
redhatrhoai/odh-trustyai-service-rhel9:17881986812026-09-08redhat
redhatdevspaces/pluginregistry-rhel9:17877597232026-09-01redhat
redhatio.netty/netty-codec-http:4.1.136.Final-redhat-000012026-07-30redhat

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 rangeFix by version rangeDependents
netty1:4.1.48-10 ... 1:4.1.48-9 (16 versions)
  • every version on: no fix on record
—
Debian:12(1)
PackageVulnerable rangeFix by version rangeDependents
netty1:4.1.48-10 ... 1:4.1.48-9 (12 versions)
  • every version on: no fix on record
—
Debian:13(1)
PackageVulnerable rangeFix by version rangeDependents
netty1:4.1.48-10 ... 1:4.1.48-16 (8 versions)
  • every version on: no fix on record
—
Debian:14(1)
PackageVulnerable rangeFix by version rangeDependents
netty1:4.1.48-10 ... 1:4.1.48-16 (7 versions)
  • every version on: no fix on record
—
Maven(1)
PackageVulnerable rangeFix by version rangeDependents
io.netty:netty-codec-http4.0.0.Alpha1 ... 4.1.99.Final (229 versions)
  • 4.2.0.Final up to 4.2.16.Final: fixed in 4.2.16.Final
  • every version up to 4.1.136.Final: fixed in 4.1.136.Final
—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 10× in last 7d / 48× in last 30d)

Each row is a time one of our pipelines fetched, updated or re-scored this CVE. 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. An arrow marks a change the record states ("CVSS v3 → 9.1"); EPSS and GHSA rows show the values recorded at that time, not what changed (EPSS values are rounded; hover one for the exact figures). Most recent first.

Showing the most recent 100 of 231 refreshes on record for this CVE.

A repeat, a row identical to one the same pipeline wrote less than 10 seconds earlier, is not a separate refresh and is not counted. None are among the latest 100 rows. The 131 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-10-26 16:31 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  2. 2026-10-25 16:33 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  3. 2026-10-25 14:16 UTCEG score recompute
  4. 2026-10-24 16:33 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  5. 2026-10-23 16:32 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  6. 2026-10-22 16:34 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  7. 2026-10-21 16:33 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  8. 2026-10-20 18:57 UTCEG score recompute
  9. 2026-10-20 18:57 UTCVendor advisory
  10. 2026-10-20 16:33 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  11. 2026-10-19 16:32 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  12. 2026-10-18 16:32 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  13. 2026-10-18 03:27 UTCEG score recompute
  14. 2026-10-17 16:35 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  15. 2026-10-16 16:43 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  16. 2026-10-15 16:32 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  17. 2026-10-14 16:33 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  18. 2026-10-13 16:34 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  19. 2026-10-13 15:48 UTCEG score recompute
  20. 2026-10-13 15:48 UTCVendor advisory
  21. 2026-10-12 16:34 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  22. 2026-10-12 15:52 UTCEG score recompute
  23. 2026-10-11 19:36 UTCEG score recompute
  24. 2026-10-11 16:51 UTCEG score recompute
  25. 2026-10-11 14:13 UTCEG score recompute
Show 75 more
  1. 2026-10-11 13:49 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  2. 2026-10-10 20:00 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  3. 2026-10-09 20:07 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  4. 2026-10-08 17:13 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  5. 2026-10-07 23:48 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  6. 2026-10-06 15:18 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  7. 2026-10-05 17:43 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  8. 2026-10-04 23:22 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  9. 2026-10-04 12:45 UTCEG score recompute
  10. 2026-10-04 12:45 UTCVendor advisory
  11. 2026-10-03 14:26 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  12. 2026-10-03 03:31 UTCEG score recompute
  13. 2026-10-03 03:31 UTCVendor advisory
  14. 2026-10-02 17:56 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  15. 2026-10-01 19:50 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  16. 2026-10-01 06:26 UTCEG score recompute
  17. 2026-10-01 06:26 UTCVendor advisory
  18. 2026-09-30 15:03 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  19. 2026-09-29 15:22 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  20. 2026-09-28 13:51 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  21. 2026-09-28 05:15 UTCEG score recompute
  22. 2026-09-28 05:15 UTCVendor advisory
  23. 2026-09-27 13:48 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  24. 2026-09-26 15:59 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  25. 2026-09-24 14:04 UTCEPSS rescoreEPSS 0.6% · 46th percentile
  26. 2026-09-24 01:30 UTCEG score recompute
  27. 2026-09-24 01:30 UTCVendor advisory
  28. 2026-09-23 17:54 UTCEPSS rescoreEPSS 0.3% · 26th percentile
  29. 2026-09-23 11:00 UTCVendor advisory
  30. 2026-09-22 23:01 UTCEG score recompute
  31. 2026-09-22 23:01 UTCVendor advisory
  32. 2026-09-20 20:16 UTCEPSS rescoreEPSS 0.3% · 26th percentile
  33. 2026-09-20 01:59 UTCEG score recompute
  34. 2026-09-20 01:59 UTCVendor advisory
  35. 2026-09-18 22:40 UTCEG score recompute
  36. 2026-09-18 22:40 UTCVendor advisory
  37. 2026-09-18 19:28 UTCEPSS rescoreEPSS 0.3% · 26th percentile
  38. 2026-09-18 03:10 UTCEG score recompute
  39. 2026-09-18 03:10 UTCVendor advisory
  40. 2026-09-17 19:31 UTCEPSS rescoreEPSS 0.3% · 26th percentile
  41. 2026-09-17 02:06 UTCEG score recompute
  42. 2026-09-17 02:06 UTCVendor advisory
  43. 2026-09-16 14:08 UTCEPSS rescoreEPSS 0.3% · 26th percentile
  44. 2026-09-16 06:58 UTCEG score recompute
  45. 2026-09-16 06:58 UTCVendor advisory
  46. 2026-09-16 05:15 UTCEPSS rescoreEPSS 0.3% · 26th percentile
  47. 2026-09-15 03:11 UTCEPSS rescoreEPSS 0.3% · 26th percentile
  48. 2026-09-14 10:24 UTCVendor advisory
  49. 2026-09-13 22:25 UTCEG score recompute
  50. 2026-09-13 22:25 UTCVendor advisory
  51. 2026-09-13 16:47 UTCEPSS rescoreEPSS 0.3% · 26th percentile
  52. 2026-09-13 09:13 UTCVendor advisory
  53. 2026-09-12 21:14 UTCEG score recompute
  54. 2026-09-12 21:14 UTCVendor advisory
  55. 2026-09-12 09:15 UTCVendor advisory
  56. 2026-09-11 21:15 UTCEG score recompute
  57. 2026-09-11 21:15 UTCVendor advisory
  58. 2026-09-11 14:53 UTCEPSS rescoreEPSS 0.3% · 26th percentile
  59. 2026-09-11 09:14 UTCVendor advisory
  60. 2026-09-10 21:15 UTCEG score recompute
  61. 2026-09-10 21:15 UTCVendor advisory
  62. 2026-09-10 09:35 UTCEPSS rescoreEPSS 0.3% · 26th percentile
  63. 2026-09-09 09:11 UTCEG score recompute
  64. 2026-09-09 09:11 UTCVendor advisory
  65. 2026-09-08 22:01 UTCEPSS rescoreEPSS 0.3% · 26th percentile
  66. 2026-09-07 21:39 UTCEG score recompute
  67. 2026-09-07 21:39 UTCVendor advisory
  68. 2026-09-07 16:01 UTCEPSS rescoreEPSS 0.3% · 26th percentile
  69. 2026-09-06 13:47 UTCEPSS rescoreEPSS 0.3% · 26th percentile
  70. 2026-09-06 08:40 UTCVendor advisory
  71. 2026-09-05 19:33 UTCEG score recompute
  72. 2026-09-05 19:33 UTCVendor advisory
  73. 2026-09-05 07:07 UTCEG score recompute
  74. 2026-09-05 07:07 UTCVendor advisory
  75. 2026-09-04 13:39 UTCEG score recompute

Frequently asked(5)

What is CVE-2026-59899?
CVE-2026-59899 is a high-severity vulnerability; its CVE record was published on July 22, 2026. Netty is an asynchronous, event-driven network application framework. Prior to versions 4.1.136.Final and 4.2.16.Final, HttpContentEncoder (the superclass of the production handler HttpContentCompressor) maintains a per-channel ArrayDeque<CharSequence> named acceptEncodingQueue that accumulates…
When was the CVE record for CVE-2026-59899 published?
The CVE record for CVE-2026-59899 was published on July 22, 2026. That is the record's publication date; the vulnerability itself may have been made public earlier. EchelonGraph's copy of the record carries a last-modified date of August 6, 2026; the record at its source may have been updated since.
Is CVE-2026-59899 actively exploited?
CVE-2026-59899 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.6% probability of exploitation in the next 30 days (48th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-59899?
CVE-2026-59899 has a CVSS v3 base score of 7.5 (NVD).
How do I remediate CVE-2026-59899?
A fix for CVE-2026-59899 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-59899 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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