Answer in brief
CVE-2026-71849 records a Low severity vulnerability in Hono: Proxy Helper does not remove response headers listed in the `Connection` header. The current sources do not mark it as known exploited. The current feed maps honojs/hono (generic), hono (npm). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
A CVSS score is not reported in the current record. 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 honojs/hono (generic), hono (npm). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| honojs/honogeneric | >= 4.7.0, < 4.12.34 | Not reported |
| hononpm | >=4.7.0,<4.12.34 | 4.12.34 |
Published upstream
Aug 7, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 7, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 7, 2026
Hono is a Web application framework that provides support for any JavaScript runtime. From 4.7.0 to 4.12.33, the Proxy Helper proxy() function in hono/proxy does not remove response headers named by the origin's Connection header. Per RFC 9110 Section 7.6.1, an intermediary must remove the header fields listed in a message's Connection header field before forwarding the message, in addition to the well known hop by hop headers, but the proxy() function only removed the well known hop by hop headers, including Connection itself, from origin responses. A client may therefore receive response headers that the origin intended only for its immediate peer, disclosing connection scoped or internal metadata contained in such headers, when an application proxies responses from an origin that declares additional, non standard headers as hop by hop via the Connection response header. This issue is fixed in version 4.12.34.
Quoted source text, attributed separately from HOL analysis.
Answer in brief
CVE-2026-71849 records a Low severity vulnerability in Hono: Proxy Helper does not remove response headers listed in the `Connection` header. The current sources do not mark it as known exploited. The current feed maps honojs/hono (generic), hono (npm). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
A CVSS score is not reported in the current record. 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 honojs/hono (generic), hono (npm). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| honojs/honogeneric | >= 4.7.0, < 4.12.34 | Not reported |
| hononpm | >=4.7.0,<4.12.34 | 4.12.34 |
Published upstream
Aug 7, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 7, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 7, 2026
Hono is a Web application framework that provides support for any JavaScript runtime. From 4.7.0 to 4.12.33, the Proxy Helper proxy() function in hono/proxy does not remove response headers named by the origin's Connection header. Per RFC 9110 Section 7.6.1, an intermediary must remove the header fields listed in a message's Connection header field before forwarding the message, in addition to the well known hop by hop headers, but the proxy() function only removed the well known hop by hop headers, including Connection itself, from origin responses. A client may therefore receive response headers that the origin intended only for its immediate peer, disclosing connection scoped or internal metadata contained in such headers, when an application proxies responses from an origin that declares additional, non standard headers as hop by hop via the Connection response header. This issue is fixed in version 4.12.34.
Quoted source text, attributed separately from HOL analysis.