Answer in brief
CVE-2026-42579 records a High severity (CVSS 7.5) vulnerability in Netty: DNS Codec Input Validation Bypass in Netty (Encoder + Decoder). The current sources do not mark it as known exploited. The current feed maps netty/netty (generic), io.netty:netty-codec-dns (maven), io.netty:netty-codec-dns (maven). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
Answer in brief
CVE-2026-42579 records a High severity (CVSS 7.5) vulnerability in Netty: DNS Codec Input Validation Bypass in Netty (Encoder + Decoder). The current sources do not mark it as known exploited. The current feed maps netty/netty (generic), io.netty:netty-codec-dns (maven), io.netty:netty-codec-dns (maven). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 7.5. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps netty/netty (generic), io.netty:netty-codec-dns (maven), io.netty:netty-codec-dns (maven). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| netty/nettygeneric | >= 4.2.0.Alpha1, < 4.2.13.Final || < 4.1.133.Final | Not reported |
| io.netty:netty-codec-dnsmaven | >=4.2.0.Alpha1,<=4.2.12.Final | 4.2.13.Final |
| io.netty:netty-codec-dnsmaven | <=4.1.132.Final | 4.1.133.Final |
Published upstream
May 13, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 6, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Jun 11, 2026
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.
Quoted source text, attributed separately from HOL analysis.
CVSS is 7.5. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps netty/netty (generic), io.netty:netty-codec-dns (maven), io.netty:netty-codec-dns (maven). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| netty/nettygeneric | >= 4.2.0.Alpha1, < 4.2.13.Final || < 4.1.133.Final | Not reported |
| io.netty:netty-codec-dnsmaven | >=4.2.0.Alpha1,<=4.2.12.Final | 4.2.13.Final |
| io.netty:netty-codec-dnsmaven | <=4.1.132.Final | 4.1.133.Final |
Published upstream
May 13, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 6, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Jun 11, 2026
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.
Quoted source text, attributed separately from HOL analysis.