CVE-2026-71849

LOWPre-NVD 3.73.7—
EchelonGraph scoreMEDIUM confidence

This low-severity CVE scores 3.7 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.4% (26th percentile of EPSS-scored CVEs). 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
3.7EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0.4%CVSS: 3.7Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

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.

CVSS v3
3.7
EG Score
3.7LOWmedium confidence
EG Risk
17
EG Risk 17/100CISA SSVC

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
Severity37% × 45%
Exploitation0% × 40%
Automatability0% × 15%
CISA SSVC: Track at every mission impact level.
Action: A fix is available. Apply it within your standard update timelines.
EPSS PROB
0.4%
EPSS %ILE
26th
KEV
Not listed

CISA SSVCTrack at every mission impact level.

A fix is available. Apply it within your standard update timelines.

Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Mission impact is CISA's Mission & Well-being decision point, and only you can judge it: high means the affected system is essential to your organisation's mission, or its compromise could cause irreversible harm to people. CISA's decision table

Published

August 7, 2026

Last Modified

September 9, 2026

References (3)

Vendor Advisories for CVE-2026-71849(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Affected Packages

(1 across 1 ecosystem)
npm(1)
PackageVulnerable rangeFix by version rangeDependents
hono—
  • 4.7.0 up to 4.12.34: fixed in 4.12.34
—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 7× in last 7d / 29× 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. 2026-10-04 23:22 UTCEPSS rescore
  2. 2026-10-04 05:43 UTCEG score recompute
  3. 2026-10-03 14:26 UTCEPSS rescore
  4. 2026-10-01 19:50 UTCEPSS rescore
  5. 2026-09-30 22:55 UTCEG score recompute
  6. 2026-09-30 15:03 UTCEPSS rescore
  7. 2026-09-28 13:52 UTCEPSS rescore
  8. 2026-09-27 17:08 UTCEG score recompute
  9. 2026-09-27 13:48 UTCEPSS rescore
  10. 2026-09-26 15:59 UTCEPSS rescore
  11. 2026-09-24 09:03 UTCEG score recompute
  12. 2026-09-23 17:54 UTCEPSS rescore
  13. 2026-09-21 21:09 UTCEPSS rescore
  14. 2026-09-21 12:03 UTCEG score recompute
  15. 2026-09-20 20:16 UTCEPSS rescore
  16. 2026-09-18 19:28 UTCEPSS rescore
  17. 2026-09-18 13:44 UTCEG score recompute
  18. 2026-09-16 14:08 UTCEPSS rescore
  19. 2026-09-16 05:15 UTCEPSS rescore
  20. 2026-09-15 16:42 UTCEG score recompute
  21. 2026-09-15 03:12 UTCEPSS rescore
  22. 2026-09-12 19:40 UTCEG score recompute
  23. 2026-09-12 15:02 UTCEPSS rescore
  24. 2026-09-11 14:53 UTCEPSS rescore
  25. 2026-09-10 09:35 UTCEPSS rescore
Show 42 more
  1. 2026-09-09 06:00 UTCEG score recompute
  2. 2026-09-08 22:01 UTCEPSS rescore
  3. 2026-09-06 13:48 UTCEPSS rescore
  4. 2026-09-06 02:59 UTCEG score recompute
  5. 2026-09-04 05:07 UTCEPSS rescore
  6. 2026-09-03 05:59 UTCEG score recompute
  7. 2026-09-02 14:12 UTCEPSS rescore
  8. 2026-09-01 13:54 UTCEPSS rescore
  9. 2026-09-01 04:40 UTCEPSS rescore
  10. 2026-08-30 19:17 UTCEPSS rescore
  11. 2026-08-30 16:48 UTCEG score recompute
  12. 2026-08-30 01:22 UTCEPSS rescore
  13. 2026-08-28 21:42 UTCEPSS rescore
  14. 2026-08-27 19:48 UTCEG score recompute
  15. 2026-08-26 14:47 UTCEPSS rescore
  16. 2026-08-25 13:49 UTCEPSS rescore
  17. 2026-08-24 22:33 UTCEG score recompute
  18. 2026-08-23 00:19 UTCEPSS rescore
  19. 2026-08-22 01:33 UTCEG score recompute
  20. 2026-08-21 23:49 UTCEPSS rescore
  21. 2026-08-20 22:56 UTCEPSS rescore
  22. 2026-08-19 17:04 UTCEPSS rescore
  23. 2026-08-19 04:32 UTCEG score recompute
  24. 2026-08-18 13:49 UTCEPSS rescore
  25. 2026-08-18 13:49 UTCEPSS rescore
  26. 2026-08-17 13:47 UTCEPSS rescore
  27. 2026-08-16 14:56 UTCEPSS rescore
  28. 2026-08-16 14:56 UTCEPSS rescore
  29. 2026-08-16 07:29 UTCEG score recompute
  30. 2026-08-16 02:15 UTCEPSS rescore
  31. 2026-08-15 01:31 UTCEPSS rescore
  32. 2026-08-13 22:00 UTCEPSS rescore
  33. 2026-08-13 10:29 UTCEG score recompute
  34. 2026-08-12 13:51 UTCEPSS rescore
  35. 2026-08-11 00:00 UTCEPSS rescore
  36. 2026-08-10 13:29 UTCEG score recompute
  37. 2026-08-10 12:24 UTCEG score recompute
  38. 2026-08-09 13:47 UTCEPSS rescore
  39. 2026-08-08 16:37 UTCEPSS rescore
  40. 2026-08-07 19:28 UTCEG score recompute
  41. 2026-08-07 18:47 UTCEG score recompute
  42. 2026-08-07 18:47 UTCMITRE cvelistV5first tracked

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Frequently asked(5)

What is CVE-2026-71849?
CVE-2026-71849 is a low vulnerability published on August 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…
When was CVE-2026-71849 disclosed?
CVE-2026-71849 was first published on August 7, 2026, with the most recent update on September 9, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-71849 actively exploited?
CVE-2026-71849 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.4% probability of exploitation in the next 30 days (26th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-71849?
CVE-2026-71849 has a CVSS base score of 3.7 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-71849?
A fix for CVE-2026-71849 is available — its CVE record says: "This issue is fixed in version 4.12.34." The vendor advisories EchelonGraph has for CVE-2026-71849 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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