CVE-2026-66752

MEDIUMPre-NVD 5.45.4—
EchelonGraph scoreHIGH confidence

Score 5.4 from GitHub Security Advisory published 2026-07-28. the CNA's CVSS baseline 5.4; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: cna:vulncheck, epss, ghsa
Trending — 3 sources updated this weekElevated
5.4EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 5.4Exploit: Elevated riskExposed: 0

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

tiny-http through 0.12.0 contains an HTTP request smuggling vulnerability that allows remote attackers to desynchronize request framing by sending a Transfer-Encoding header with any value, including non-chunked codings, which causes the library to unconditionally apply chunk-decoding and discard Content-Length. Attackers can exploit the discrepancy between tiny_http's improper Transfer-Encoding parsing and a correctly-implemented front-end proxy to produce two distinct interpretations of a single byte stream, enabling request smuggling, and can additionally send non-chunked bodies with non-chunked Transfer-Encoding values to cause failed body reads that tie up connections and consume worker threads without signaling errors to clients.

CVSS v3
5.4
EG Score
5.4(high)
EG Risk
40(Track)
EG Risk 40/100SSVC: 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
Severity54% × 45%
Exploitation40% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
14%
KEV
Not listed

Published

July 28, 2026

Last Modified

August 14, 2026

Advisory Details (2)

Auto-updated Jul 28, 2026
🔬 Proof of concept available. No patch confirmed yet.
generic

tiny-http 0.12.0 HTTP Request Smuggling via Transfer-Encoding Handling | Advisories | VulnCheck

https://www.vulncheck.com/advisories/tiny-http-http-request-smuggling-via-transfer-encoding-handling
generic🟡 PoC Available

GitHub - theopaid/HTTP-Request-Smuggling-via-Unparsed-Transfer-Encoding-Values-tiny_http-: Security Advisory: HTTP Request Smuggling via Unparsed Transfer-Encoding Values (tiny_http) · GitHub

https://github.com/theopaid/HTTP-Request-Smuggling-via-Unparsed-Transfer-Encoding-Values-tiny_http-/tree/master

Vendor Advisories for CVE-2026-66752(1)

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

Affected Packages

(3 across 3 ecosystems)
Debian:12(1)
PackageVulnerable rangeFixed inDependents
rust-tiny-http0.12.0-1——
Debian:13(1)
PackageVulnerable rangeFixed inDependents
rust-tiny-http0.12.0-1——
Debian:14(1)
PackageVulnerable rangeFixed inDependents
rust-tiny-http0.12.0-1——

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 20× in last 7d / 89× 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. 2026-08-26 03:22 UTCEG score recompute
  2. 2026-08-26 03:22 UTCGHSA enrichment
  3. 2026-08-25 13:49 UTCEPSS rescore
  4. 2026-08-25 04:20 UTCEG score recompute
  5. 2026-08-25 04:20 UTCGHSA enrichment
  6. 2026-08-24 05:35 UTCGHSA enrichment
  7. 2026-08-23 06:51 UTCEG score recompute
  8. 2026-08-23 06:51 UTCGHSA enrichment
  9. 2026-08-23 00:19 UTCEPSS rescore
  10. 2026-08-22 08:05 UTCEG score recompute
  11. 2026-08-22 08:05 UTCGHSA enrichment
  12. 2026-08-21 23:49 UTCEPSS rescore
  13. 2026-08-21 09:20 UTCEG score recompute
  14. 2026-08-21 09:20 UTCGHSA enrichment
  15. 2026-08-20 22:56 UTCEPSS rescore
  16. 2026-08-20 10:34 UTCEG score recompute
  17. 2026-08-20 10:34 UTCGHSA enrichment
  18. 2026-08-19 17:04 UTCEPSS rescore
  19. 2026-08-19 11:49 UTCEG score recompute
  20. 2026-08-19 11:49 UTCGHSA enrichment
  21. 2026-08-18 13:48 UTCEPSS rescore
  22. 2026-08-18 13:04 UTCEG score recompute
  23. 2026-08-18 13:04 UTCGHSA enrichment
  24. 2026-08-17 13:47 UTCEPSS rescore
  25. 2026-08-17 13:27 UTCEG score recompute
Show 64 more
  1. 2026-08-17 13:27 UTCGHSA enrichment
  2. 2026-08-16 14:56 UTCEPSS rescore
  3. 2026-08-16 14:42 UTCEG score recompute
  4. 2026-08-16 14:42 UTCGHSA enrichment
  5. 2026-08-15 15:57 UTCEG score recompute
  6. 2026-08-15 15:57 UTCGHSA enrichment
  7. 2026-08-15 01:30 UTCEPSS rescore
  8. 2026-08-14 17:12 UTCEG score recompute
  9. 2026-08-14 17:12 UTCGHSA enrichment
  10. 2026-08-14 03:08 UTCEG score recompute
  11. 2026-08-14 03:08 UTCGHSA enrichment
  12. 2026-08-13 22:00 UTCEPSS rescore
  13. 2026-08-13 04:24 UTCEG score recompute
  14. 2026-08-13 04:24 UTCGHSA enrichment
  15. 2026-08-12 13:51 UTCEPSS rescore
  16. 2026-08-12 05:39 UTCEG score recompute
  17. 2026-08-12 05:39 UTCGHSA enrichment
  18. 2026-08-11 06:47 UTCEG score recompute
  19. 2026-08-11 06:47 UTCGHSA enrichment
  20. 2026-08-11 00:00 UTCEPSS rescore
  21. 2026-08-10 08:03 UTCEG score recompute
  22. 2026-08-10 08:03 UTCGHSA enrichment
  23. 2026-08-09 13:47 UTCEPSS rescore
  24. 2026-08-09 09:18 UTCEG score recompute
  25. 2026-08-09 09:18 UTCGHSA enrichment
  26. 2026-08-08 16:37 UTCEPSS rescore
  27. 2026-08-08 10:33 UTCEG score recompute
  28. 2026-08-08 10:32 UTCGHSA enrichment
  29. 2026-08-07 11:47 UTCEG score recompute
  30. 2026-08-07 11:47 UTCGHSA enrichment
  31. 2026-08-06 13:47 UTCEPSS rescore
  32. 2026-08-06 13:02 UTCEG score recompute
  33. 2026-08-06 13:02 UTCGHSA enrichment
  34. 2026-08-05 19:17 UTCEPSS rescore
  35. 2026-08-05 19:17 UTCEPSS rescore
  36. 2026-08-05 14:17 UTCEG score recompute
  37. 2026-08-05 14:17 UTCGHSA enrichment
  38. 2026-08-04 15:10 UTCEPSS rescore
  39. 2026-08-04 14:01 UTCEG score recompute
  40. 2026-08-04 14:01 UTCGHSA enrichment
  41. 2026-08-04 10:39 UTCEPSS rescore
  42. 2026-08-03 15:16 UTCEG score recompute
  43. 2026-08-03 15:16 UTCGHSA enrichment
  44. 2026-08-03 10:36 UTCEPSS rescore
  45. 2026-08-02 16:28 UTCEG score recompute
  46. 2026-08-02 16:28 UTCGHSA enrichment
  47. 2026-08-02 02:27 UTCEPSS rescore
  48. 2026-08-01 17:43 UTCEG score recompute
  49. 2026-08-01 17:43 UTCGHSA enrichment
  50. 2026-08-01 04:16 UTCEPSS rescore
  51. 2026-07-31 18:58 UTCGHSA enrichment
  52. 2026-07-30 20:14 UTCEG score recompute
  53. 2026-07-30 20:13 UTCGHSA enrichment
  54. 2026-07-30 16:28 UTCEPSS rescore
  55. 2026-07-30 15:57 UTCEG score recompute
  56. 2026-07-30 15:57 UTCGHSA enrichment
  57. 2026-07-30 01:30 UTCEPSS rescore
  58. 2026-07-29 17:11 UTCEG score recompute
  59. 2026-07-29 17:11 UTCGHSA enrichment
  60. 2026-07-28 17:23 UTCEG score recompute▼ 1.80
  61. 2026-07-28 17:21 UTCNVD updateCVSS v3 → 5.4 · severity → MEDIUM
  62. 2026-07-28 16:40 UTCEG score recompute
  63. 2026-07-28 16:14 UTCEG score recompute
  64. 2026-07-28 16:13 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-66752?
CVE-2026-66752 is a medium vulnerability published on July 28, 2026. tiny-http through 0.12.0 contains an HTTP request smuggling vulnerability that allows remote attackers to desynchronize request framing by sending a Transfer-Encoding header with any value, including non-chunked codings, which causes the library to unconditionally apply chunk-decoding and discard…
When was CVE-2026-66752 disclosed?
CVE-2026-66752 was first published in the National Vulnerability Database on July 28, 2026, with the most recent update on August 14, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-66752 actively exploited?
CVE-2026-66752 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 85.5% of all scored CVEs.
What is the CVSS score of CVE-2026-66752?
CVE-2026-66752 has a CVSS v4.0 base score of 5.4 (CNA self-assessment; NVD's own analysis pending).
How do I remediate CVE-2026-66752?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-66752, 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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