Netty is an asynchronous, event-driven network application framework. Prior to 4.2.13.Final and 4.1.133.Final, Netty's DNS codec does not enforce RFC 1035 domain name constraints during either encoding or decoding. This creates a bidirectional attack surface: malicious DNS responses can exploit the decoder, and user-influenced hostnames can exploit the encoder. This vulnerability is fixed in 4.2.13.Final and 4.1.133.Final.
CVE-2026-42579
“—” beside the score: it is equal to NVD's CVSS score.
This critical-severity CVE scores 9.1 under NVD CVSS v3. EPSS exploit probability: 1.0% (63rd percentile of EPSS-scored CVEs). GitHub Security Advisory CVSS 7.5 is lower than this score; a lower GitHub score revises it only when its advisory is newer than the CVE record's last change, and this advisory (published 2026-05-07) is not newer than that change (2026-09-18), so it does not.
Also known asEUVD-2026-30122 (ENISA EUVD) · GHSA-cm33-6792-r9fm (GitHub Security Advisories)Source: ENISA EUVD
- CISA's Vulnrichment rates exploitation as PoC; EchelonGraph holds no exploit-code reference for it
A fix is available — apply it.
- CVSS v3
- 9.1
- EG Score
- 9.1CRITICALmedium confidence
- EG Risk
- 72EG Risk 72/100
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)Severity91% × 45%Impact severity (EG Severity): CVSS 9.1 of 10. Never the KEV-floored or EPSS-lifted EG Score.Exploitation40% × 40%EchelonGraph's fixed weight for EG-KEV Tier 3 (Elevated): a constant, not a probability.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 public PoC (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
- 1.0%
- EPSS %ILE
- 63rd
- 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 (9.1): severity, escalated by confirmed exploitation. This CVE's 9.1 is its impact severity (EG Severity), not escalated.
- EG Severity
- 9.1 CRITICALCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.NVD CVSS v3 · CVSS v3.0 or v3.1
- EG Likelihood
- 1.0% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-11-01). 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, and whom BOD 26-04 binds: 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 public PoC (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.
The score's inputs: 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
May 13, 2026
Last Modified
September 18, 2026
Advisory Details (11)
Auto-updated Sep 15, 2026Affected: Red Hat Enterprise Linux 7. Red Hat Product Security has rated
https://access.redhat.com/errata/RHSA-2026:53644DNS Codec Input Validation Bypass in Netty (Encoder + Decoder) · Advisory · netty/netty · GitHub
https://github.com/netty/netty/security/advisories/GHSA-cm33-6792-r9fmVendor Advisories for CVE-2026-42579(20)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
- RHSA-2026:84734Red Hat Product SecurityCritical
Red Hat Security Advisory: RHOAI 3.4.5 - Red Hat OpenShift AI
- RHSA-2026:76128Red Hat Product SecurityHigh
Red Hat Security Advisory: Red Hat Single Sign-On 7.6.13 security update on RHEL 7
- RHSA-2026:76130Red Hat Product SecurityHigh
Red Hat Security Advisory: Red Hat Single Sign-On 7.6.13 security update on RHEL 9
- RHSA-2026:76129Red Hat Product SecurityHigh
Red Hat Security Advisory: Red Hat Single Sign-On 7.6.13 security update on RHEL 8
- RHSA-2026:76134Red Hat Product SecurityHigh
Red Hat Security Advisory: Red Hat Single Sign-On 7.6.13 for OpenShift image security update
- RHSA-2026:76132Red Hat Product SecurityHigh
Red Hat Security Advisory: Red Hat Single Sign-On 7.6.13 security update
- RHSA-2026:65126Red Hat Product SecurityHigh
Red Hat Security Advisory: RHOAI 2.25.11 - Red Hat OpenShift AI
- RHSA-2026:54435Red Hat Product SecurityHigh
Red Hat Security Advisory: Streams for Apache Kafka 3.2.1 release and security update
- +12 more
Patch Availability(20)
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)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| netty | 1:4.1.48-10 ... 1:4.1.48-9 (16 versions) |
| — |
Debian:12(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| netty | 1:4.1.48-10 ... 1:4.1.48-9 (12 versions) |
| — |
Debian:13(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| netty | 1:4.1.48-10 ... 1:4.1.48-16 (8 versions) |
| — |
Debian:14(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| netty | 1:4.1.48-10 ... 1:4.1.48-16 (7 versions) |
| — |
Maven(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| io.netty:netty-codec-dns | 4.1.0.Beta1 ... 4.1.99.Final (148 versions) |
| — |
Weakness Classification(4)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Additional Vendor Advisories
(2)
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 26× in last 7d / 82× 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 352 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 252 oldest rows on record are not shown and were not checked, so the counts can still include repeats.
- 2026-11-01 22:26 UTCEG score recompute
- 2026-11-01 22:26 UTCVendor advisory
- 2026-11-01 22:26 UTCGHSA enrichmentGHSA-cm33-6792-r9fm · GitHub severity HIGH · GitHub CVSS 7.5
- 2026-11-01 16:34 UTCEPSS rescoreEPSS 1.0% · 63rd percentile
- 2026-11-01 07:50 UTCGHSA enrichmentGHSA-cm33-6792-r9fm · GitHub severity HIGH · GitHub CVSS 7.5
- 2026-11-01 07:50 UTCEG score recompute
- 2026-11-01 00:50 UTCEG score recompute
- 2026-11-01 00:50 UTCVendor advisory
- 2026-10-31 16:32 UTCEPSS rescoreEPSS 1.0% · 63rd percentile
- 2026-10-31 03:12 UTCEG score recompute
- 2026-10-31 03:12 UTCVendor advisory
- 2026-10-30 16:34 UTCEPSS rescoreEPSS 1.0% · 62nd percentile
- 2026-10-30 05:35 UTCEG score recompute
- 2026-10-30 05:35 UTCVendor advisory
- 2026-10-29 16:33 UTCEPSS rescoreEPSS 1.0% · 62nd percentile
- 2026-10-29 07:58 UTCEG score recompute
- 2026-10-29 07:58 UTCVendor advisory
- 2026-10-28 16:32 UTCEPSS rescoreEPSS 1.0% · 62nd percentile
- 2026-10-28 10:20 UTCEG score recompute
- 2026-10-28 10:20 UTCVendor advisory
- 2026-10-27 16:32 UTCEPSS rescoreEPSS 1.0% · 62nd percentile
- 2026-10-27 11:47 UTCEG score recompute
- 2026-10-27 11:47 UTCVendor advisory
- 2026-10-26 16:31 UTCEPSS rescoreEPSS 1.0% · 62nd percentile
- 2026-10-26 14:11 UTCEG score recompute
Show 75 moreShow fewer
- 2026-10-26 14:11 UTCVendor advisory
- 2026-10-25 16:33 UTCEPSS rescoreEPSS 1.0% · 62nd percentile
- 2026-10-25 16:04 UTCVendor advisory
- 2026-10-25 14:29 UTCEG score recompute
- 2026-10-24 18:26 UTCEG score recompute
- 2026-10-24 18:26 UTCVendor advisory
- 2026-10-24 16:33 UTCEPSS rescoreEPSS 0.8% · 57th percentile
- 2026-10-23 20:49 UTCEG score recompute
- 2026-10-23 20:49 UTCVendor advisory
- 2026-10-23 16:31 UTCEPSS rescoreEPSS 0.8% · 57th percentile
- 2026-10-22 22:56 UTCEG score recompute
- 2026-10-22 22:56 UTCVendor advisory
- 2026-10-22 16:34 UTCEPSS rescoreEPSS 0.8% · 57th percentile
- 2026-10-22 01:19 UTCEG score recompute
- 2026-10-22 01:19 UTCVendor advisory
- 2026-10-21 16:33 UTCEPSS rescoreEPSS 0.8% · 57th percentile
- 2026-10-21 03:26 UTCEG score recompute
- 2026-10-21 03:26 UTCVendor advisory
- 2026-10-20 16:33 UTCEPSS rescoreEPSS 0.8% · 57th percentile
- 2026-10-20 05:30 UTCEG score recompute
- 2026-10-20 05:30 UTCVendor advisory
- 2026-10-19 16:32 UTCEPSS rescoreEPSS 0.8% · 57th percentile
- 2026-10-19 06:59 UTCEG score recompute
- 2026-10-19 06:59 UTCVendor advisory
- 2026-10-18 16:32 UTCEPSS rescoreEPSS 0.8% · 57th percentile
- 2026-10-18 09:19 UTCVendor advisory
- 2026-10-18 03:40 UTCEG score recompute
- 2026-10-17 16:34 UTCEPSS rescoreEPSS 0.8% · 57th percentile
- 2026-10-17 10:53 UTCEG score recompute
- 2026-10-17 10:53 UTCVendor advisory
- 2026-10-16 16:42 UTCEPSS rescoreEPSS 0.8% · 57th percentile
- 2026-10-16 12:28 UTCEG score recompute
- 2026-10-16 12:28 UTCVendor advisory
- 2026-10-15 16:32 UTCEPSS rescoreEPSS 0.8% · 57th percentile
- 2026-10-15 14:15 UTCEG score recompute
- 2026-10-15 14:15 UTCVendor advisory
- 2026-10-14 16:33 UTCEPSS rescoreEPSS 0.8% · 57th percentile
- 2026-10-14 08:59 UTCEG score recompute
- 2026-10-14 08:59 UTCVendor advisory
- 2026-10-13 16:34 UTCEPSS rescoreEPSS 0.8% · 56th percentile
- 2026-10-13 05:35 UTCEG score recompute
- 2026-10-13 05:35 UTCVendor advisory
- 2026-10-12 16:34 UTCEPSS rescoreEPSS 0.8% · 56th percentile
- 2026-10-12 16:07 UTCEG score recompute
- 2026-10-12 07:57 UTCVendor advisory
- 2026-10-11 19:49 UTCEG score recompute
- 2026-10-11 17:03 UTCEG score recompute
- 2026-10-11 14:29 UTCEG score recompute
- 2026-10-11 13:48 UTCEPSS rescoreEPSS 0.8% · 56th percentile
- 2026-10-10 20:00 UTCEPSS rescoreEPSS 0.8% · 56th percentile
- 2026-10-09 20:07 UTCEPSS rescoreEPSS 0.8% · 56th percentile
- 2026-10-08 17:12 UTCEPSS rescoreEPSS 0.8% · 56th percentile
- 2026-10-08 07:35 UTCOSV refresh
- 2026-10-07 23:48 UTCEPSS rescoreEPSS 0.8% · 56th percentile
- 2026-10-06 15:17 UTCEPSS rescoreEPSS 0.8% · 56th percentile
- 2026-10-05 17:43 UTCEPSS rescoreEPSS 0.8% · 56th percentile
- 2026-10-03 14:25 UTCEPSS rescoreEPSS 0.8% · 56th percentile
- 2026-10-01 19:50 UTCEPSS rescoreEPSS 0.8% · 56th percentile
- 2026-09-30 15:03 UTCEPSS rescoreEPSS 0.8% · 56th percentile
- 2026-09-27 13:48 UTCEPSS rescoreEPSS 0.8% · 56th percentile
- 2026-09-26 15:58 UTCEPSS rescoreEPSS 0.8% · 56th percentile
- 2026-09-23 17:53 UTCEPSS rescoreEPSS 1.0% · 61st percentile
- 2026-09-18 19:28 UTCEPSS rescoreEPSS 1.0% · 61st percentile
- 2026-09-18 13:23 UTCVendor advisory
- 2026-09-18 12:20 UTCEG score recompute
- 2026-09-18 12:20 UTCVendor advisory
- 2026-09-17 19:31 UTCEPSS rescoreEPSS 1.0% · 61st percentile
- 2026-09-17 12:20 UTCVendor advisory
- 2026-09-17 12:11 UTCEG score recompute
- 2026-09-17 12:11 UTCVendor advisory
- 2026-09-16 14:08 UTCEPSS rescoreEPSS 1.0% · 61st percentile
- 2026-09-16 05:15 UTCEPSS rescoreEPSS 1.0% · 61st percentile
- 2026-09-12 15:01 UTCEPSS rescoreEPSS 1.0% · 61st percentile
- 2026-09-11 14:53 UTCEPSS rescoreEPSS 1.0% · 61st percentile
- 2026-09-11 09:37 UTCEPSS rescoreEPSS 1.0% · 60th percentile
Related CVEs(same product + same vendor + same CWE)
Same product
10 shownMaven:io.netty:netty-codec-dns · Debian:11:netty
- CVE-2026-73508EG 7.5HIGH
- CVE-2026-47691EG 10.0CRITICAL
- CVE-2026-45674EG 10.0CRITICAL
- CVE-2026-56817EG 9.8CRITICAL
- CVE-2026-42581EG 9.8CRITICAL
- CVE-2026-56820EG 9.1CRITICAL
- CVE-2026-42584EG 9.1CRITICAL
- CVE-2019-20445EG 9.1EPSS p97CRITICAL
- CVE-2019-20444EG 9.1EPSS p95CRITICAL
- CVE-2023-44487NVD 7.5EG 9.0 KEVEPSS p100CRITICAL
Same vendor
10 shownredhat:RHSA-2026:23808 · redhat:RHSA-2026:30049
Frequently asked(5)
What is CVE-2026-42579?
When was the CVE record for CVE-2026-42579 published?
Is CVE-2026-42579 actively exploited?
What is the CVSS score of CVE-2026-42579?
How do I remediate CVE-2026-42579?
Dependency Blast Radius
See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-42579
Is Your Infrastructure Affected by CVE-2026-42579?
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