CVE-2026-71848

MEDIUMPre-NVD 5.35.3—
EchelonGraph scoreMEDIUM confidence

This medium-severity CVE scores 5.3 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.3%, top 78% of all CVEs by exploit prediction. 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
5.3EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 5.3Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

Hono is a Web application framework that provides support for any JavaScript runtime. From 4.12.0 to 4.12.33, the languageDetector middleware is vulnerable to algorithmic complexity denial of service when processing a crafted language tag containing a large number of hyphen separated subtags. To implement progressive language tag truncation, normalizeLanguage() repeatedly calls parts.slice(0, i).join('-') for every possible prefix, so the total amount of string processing grows quadratically with the number of subtags. Language values may come from a query parameter, cookie, Accept-Language header, or URL path, depending on the detector configuration, and the default detector order enables query string, cookie, and header detection, so applications using languageDetector() may expose this processing to unauthenticated requests. An attacker may repeatedly send requests containing long, hyphen separated language tags, causing excessive CPU consumption and preventing unrelated requests from being processed. This issue is fixed in version 4.12.34.

CVSS v3
5.3
EG Score
5.3(medium)
EG Risk
39(Track)
EG Risk 39/100SSVC: Track

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
Severity53% × 45%
Exploitation0% × 40%
Automatability100% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
22%
KEV
Not listed

Published

August 7, 2026

Last Modified

August 8, 2026

Advisory Details (3)

Auto-updated Aug 7, 2026
Patch available. Sources: github, github_commit, github_release.
github_release Patch Available

v4.12.34

Patch available: honojs/hono v4.12.34

https://github.com/honojs/hono/releases/tag/v4.12.34
github_commit Patch Available

commit f70e2c316843 (honojs/hono)

Patch available: honojs/hono v4.12.34 (contains commit f70e2c316843)

https://github.com/honojs/hono/commit/f70e2c31684387b3231cc38512a31df6ca76a1c7
github Patch Available

Algorithmic Complexity DoS in Language Middleware · Advisory · honojs/hono · GitHub

https://github.com/honojs/hono/security/advisories/GHSA-54fx-42gc-7vw4

Vendor Advisories for CVE-2026-71848(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 rangeFixed inDependents
hono—4.12.34—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 15× in last 7d / 30× 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. 2026-08-20 22:56 UTCEPSS rescore
  2. 2026-08-19 18:47 UTCEG score recompute
  3. 2026-08-19 17:04 UTCEPSS rescore
  4. 2026-08-18 17:25 UTCEG score recompute
  5. 2026-08-18 13:49 UTCEPSS rescore
  6. 2026-08-18 13:49 UTCEPSS rescore
  7. 2026-08-17 15:22 UTCEG score recompute
  8. 2026-08-17 13:47 UTCEPSS rescore
  9. 2026-08-16 14:56 UTCEPSS rescore
  10. 2026-08-16 14:56 UTCEPSS rescore
  11. 2026-08-16 14:09 UTCEG score recompute
  12. 2026-08-16 02:15 UTCEPSS rescore
  13. 2026-08-15 12:56 UTCEG score recompute
  14. 2026-08-15 01:31 UTCEPSS rescore
  15. 2026-08-14 11:43 UTCEG score recompute
  16. 2026-08-13 22:00 UTCEPSS rescore
  17. 2026-08-13 10:30 UTCEG score recompute
  18. 2026-08-12 13:51 UTCEPSS rescore
  19. 2026-08-12 09:17 UTCEG score recompute
  20. 2026-08-11 08:03 UTCEG score recompute
  21. 2026-08-11 00:00 UTCEPSS rescore
  22. 2026-08-10 06:50 UTCEG score recompute
  23. 2026-08-09 13:47 UTCEPSS rescore
  24. 2026-08-09 05:37 UTCEG score recompute
  25. 2026-08-08 16:37 UTCEPSS rescore
Show 5 more
  1. 2026-08-08 04:24 UTCEG score recompute
  2. 2026-08-08 03:27 UTCEG score recompute
  3. 2026-08-07 19:28 UTCEG score recompute
  4. 2026-08-07 18:47 UTCEG score recompute
  5. 2026-08-07 18:47 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-71848?
CVE-2026-71848 is a medium vulnerability published on August 7, 2026. Hono is a Web application framework that provides support for any JavaScript runtime. From 4.12.0 to 4.12.33, the languageDetector middleware is vulnerable to algorithmic complexity denial of service when processing a crafted language tag containing a large number of hyphen separated subtags. To…
When was CVE-2026-71848 disclosed?
CVE-2026-71848 was first published in the National Vulnerability Database on August 7, 2026, with the most recent update on August 8, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-71848 actively exploited?
CVE-2026-71848 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 78.2% of all scored CVEs.
What is the CVSS score of CVE-2026-71848?
CVE-2026-71848 has a CVSS v3 base score of 5.3 (NVD).
How do I remediate CVE-2026-71848?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-71848, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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