CVE-2026-48710

CRITICALNVD 6.59.0
EchelonGraph scoreHIGH confidence

“▲” beside the score: it is higher than NVD's CVSS score.

Score elevated to 9.0 because this CVE is listed on the CISA Known Exploited Vulnerabilities catalog (added 2026-09-02), indicating real-world exploitation has been confirmed by US federal agencies. NVD baseline CVSS 6.5 retained for reference. The 9.0 is the floor for confirmed exploitation, not an impact rating: this CVE's impact severity (EG Severity) is CVSS 6.5 MEDIUM under NVD CVSS v3. Confidence: HIGH.

Triggered by: CISA KEV (actively exploited)
Sources: CISA Known Exploited Vulnerabilities catalog, EPSS, NVD CVSS v3
Trending — Patch released this weekExploited in the wild
9.0EG
EchelonGraph verdictPatch nowTreat as an emergency — this is being exploited.
  • Actively exploited in the wild (CISA-KEV) — the reason this is sooner than the SSVC decision on this page at low or medium mission impact
CISA-KEV: ExploitedEPSS PROB: 7.1%CVSS: 6.5Exploit: No code on recordExposed services: Not assessed

A fix is available — apply it.

Starlette is a lightweight ASGI framework/toolkit. Prior to version 1.0.1, the HTTP Host request header was not validated before being used to reconstruct request.url. Because the routing algorithm relies on the raw HTTP path while request.url is rebuilt from the Host header, a malformed header could make request.url.path differ from the path that was actually requested. Middleware and endpoints that apply security restrictions based on request.url (rather than the raw scope path) could therefore be bypassed. Users should upgrade to a version greater than or equal to version 1.0.1, which validates the Host header against the grammar of RFC 9112 §3.2 / RFC 3986 §3.2.2 when constructing request.url and falls back to scope["server"] for malformed values.

CVSS v3
6.5
EG Score
9.0CRITICALhigh confidence
EG Risk
84
EG Risk 84/100

EG Risk is EchelonGraph's 0–100 priority score. It fuses impact severity (EG Severity, the CVSS base score, never the KEV-floored or EPSS-lifted EG Score) with real-world exploitation and automatability, under weights EchelonGraph set by hand, so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner.

How it’s computed (value × EchelonGraph’s weight)
Severity65% × 45%
Impact severity (EG Severity): CVSS 6.5 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation100% × 40%
Fixed at 100% for a CISA KEV listing: EchelonGraph's rule.
Automatability100% × 15%
CISA's SSVC Automatable value: yes (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Attend at low or medium mission impact; Act at high (mission-essential systems).
Exploitation active (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE.
Action: A fix is available. Apply it sooner than your standard update timelines at low or medium mission impact and as soon as possible at high.
EPSS PROB
7.1%
EPSS %ILE
94th
KEV
⚠ Exploited

What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)

The EG score (9.0): severity, escalated by confirmed exploitation. This CVE's 9.0 is the CISA KEV floor for confirmed exploitation, not an impact rating: its impact severity (EG Severity) is CVSS 6.5 MEDIUM.

EG Severity
6.5 MEDIUMCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.NVD CVSS v3 · CVSS v3.0 or v3.1
EG Likelihood
7.1% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-20). FIRST's exploitation probability, not an EchelonGraph model.
Confirmed exploitation
CISA KEV and EG-KEV Tier 1 (exploited in the wild)Reported apart from the likelihood: an observed fact, not a probability.
EG Priority
SSVC Attend at medium mission impactAttend at low or medium mission impact; Act at high (mission-essential systems).CISA BOD 26-04: 3 days if the affected system is publicly exposed; 14 days if it is not.Each input and its source: the SSVC and BOD 26-04 blocks below.

SSVC (CISA's decision table, applied by EchelonGraph)Attend at low or medium mission impact; Act at high (mission-essential systems).

A fix is available. Apply it sooner than your standard update timelines at low or medium mission impact and as soon as possible at high.

Exploitation active (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table

BOD 26-04 (CISA's remediation timeline, Table 1)3 days if the affected system is publicly exposed; 14 days if it is not.

In CISA KEV yes (CISA's KEV catalog) · Automatable yes (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it

CISA required action“Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.”

Quoted verbatim from CISA's Known Exploited Vulnerabilities catalog. CISA directs it at US federal civilian executive branch agencies under Binding Operational Directive (BOD) 26-04, which replaced BOD 22-01 on 10 June 2026; it is not EchelonGraph's advice. CISA's notes: https://github.com/Kludex/starlette/security/advisories/GHSA-86qp-5c8j-p5mr · https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk · https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk · https://nvd.nist.gov/vuln/detail/CVE-2026-48710

Published

May 26, 2026

Last Modified

October 1, 2026

Advisory Details (10)

Auto-updated Oct 20, 2026
⚠️ Actively exploited (CISA KEV, CISA Vulnrichment). Patch available. Sources: redhat, github_commit, github.
Red HatMentions a patch (unverified)
https://access.redhat.com/errata/RHSA-2026:23346
Red HatMentions a patch (unverified)
https://access.redhat.com/errata/RHSA-2026:22993
Red HatMentions a patch (unverified)
https://access.redhat.com/errata/RHSA-2026:22992
Web page

Advisory X41-2026-002: Request Host Header not Validated in Starlette | X41 D-Sec - Penetration Tests and Source Code Audits

https://www.x41-dsec.de/lab/advisories/x41-2026-002-starlette
Web page🟡 PoC Available

starlette - secwest.net - secure virtual engagement

https://www.secwest.net/starlette
Web page

Disclosing the BADHOST Vulnerability in Starlette – OSTIF.org

https://ostif.org/disclosing-the-badhost-vulnerability-in-starlette
Web page

advisory-database/vulns/starlette/PYSEC-2026-161.yaml at main · pypa/advisory-database · GitHub

https://github.com/pypa/advisory-database/tree/main/vulns/starlette/PYSEC-2026-161.yaml
GitHub advisoryMentions a patch (unverified)

Missing Host header validation poisons request.url.path, bypassing path-based security checks · Advisory · Kludex/starlette · GitHub

https://github.com/Kludex/starlette/security/advisories/GHSA-86qp-5c8j-p5mr
GitHub commit Patch Available

commit 764dab0dcfb9 (Kludex/starlette)

Patch available: Kludex/starlette 1.0.1 (contains commit 764dab0dcfb9)

https://github.com/Kludex/starlette/commit/764dab0dcfb9033d75442d7a359645c9f94648c6
Web page

BadHost - CVE-2026-48710 Starlette Host-Header Auth Bypass

https://badhost.org

Patch Availability(26)

Vendor / EcosystemFix (by version range) / PatchReleasedSource
redhatrhoai/odh-kserve-autogluon-server-rhel9:17913000232026-10-19redhat
redhatrhelai3/bootc-gcp-cuda-rhel9:17908811232026-10-05redhat
redhatrhelai3/disk-image-cuda-rhel9:17909574172026-10-05redhat
redhatrhoai/odh-trustyai-garak-lls-provider-dsp-rhel9:17900853102026-09-30redhat
redhatrhaii/vllm-cuda-rhel9:17900901312026-09-23redhat
redhatrhaii/vllm-spyre-rhel9:17900761412026-09-23redhat
redhatrhaii/vllm-cpu-rhel9:17900757932026-09-23redhat
redhatrhaii/vllm-cpu-rhel9:17896811282026-09-21redhat
redhatrhaii/vllm-spyre-rhel9:17896812012026-09-21redhat
redhatrhaii/vllm-cuda-rhel9:17896811262026-09-21redhat
redhatsatellite/iop-vulnerability-engine-rhel9:17881902242026-09-03redhat
redhatrhoai/odh-feature-server-rhel9:17870680652026-08-27redhat
redhatsatellite/iop-vulnerability-engine-rhel9:17845541232026-08-06redhat
redhatsatellite/iop-advisor-engine-rhel9:17848344022026-07-23redhat
redhatmta/mta-solution-server-rhel9:17841098832026-07-21redhat
redhatrhoai/odh-workbench-jupyter-tensorflow-cuda-py312-rhel9:17824717302026-07-09redhat
redhatsatellite/iop-vmaas-rhel9:17821396192026-07-01redhat
redhatrhoai/odh-workbench-jupyter-trustyai-cpu-py312-rhel9:17821353002026-07-01redhat
redhatsatellite/iop-host-inventory-rhel9:17804030262026-07-01redhat
redhatrhaiis/vllm-cuda-rhel9:17823528472026-06-25redhat
redhatrhaiis/vllm-rocm-rhel9:17823530932026-06-25redhat
redhatsatellite/iop-host-inventory-rhel9:17804142372026-06-16redhat
redhatansible-automation-platform-26/lightspeed-chatbot-rhel9:17801027322026-06-09redhat
redhatansible-automation-platform-27/lightspeed-chatbot-rhel9:17800991852026-06-04redhat
redhatsatellite/foreman-mcp-server-rhel9:17804920082026-06-03redhat
redhatsatellite/foreman-mcp-server-rhel9:17804920122026-06-03redhat

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Affected Packages

(5 across 5 ecosystems)
Debian:11(1)
PackageVulnerable rangeFix by version rangeDependents
starlette0.14.1-1 ... 1.3.1-1 (27 versions)
  • every version on: no fix on record
—
Debian:12(1)
PackageVulnerable rangeFix by version rangeDependents
starlette0.26.1-1
  • every version up to 0.26.1-1+deb12u1: fixed in 0.26.1-1+deb12u1
—
Debian:13(1)
PackageVulnerable rangeFix by version rangeDependents
starlette0.46.1-3, 0.46.1-3+deb13u1
  • every version up to 0.46.1-3+deb13u2: fixed in 0.46.1-3+deb13u2
—
Debian:14(1)
PackageVulnerable rangeFix by version rangeDependents
starlette0.46.1-3, 0.50.0-1, 1.0.0-1
  • every version up to 1.1.0-1: fixed in 1.1.0-1
—
PyPI(1)
PackageVulnerable rangeFix by version rangeDependents
starlette0.1.0 ... 1.0.0rc1 (191 versions)
  • every version up to 1.0.1: fixed in 1.0.1
—

Weakness Classification(2)

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

Additional Vendor Advisories

(6)

Data Freshness Timeline

(refreshed 22× in last 7d / 200× in last 30d)

Each row is a time one of our pipelines fetched, updated or re-scored this CVE. 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. An arrow marks a change the record states ("CVSS v3 → 9.1"); EPSS and GHSA rows show the values recorded at that time, not what changed (EPSS values are rounded; hover one for the exact figures). Most recent first.

Showing the most recent 100 of 557 refreshes on record for this CVE.

A repeat, a row identical to one the same pipeline wrote less than 10 seconds earlier, is not a separate refresh and is not counted. None are among the latest 100 rows. The 457 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-10-21 16:33 UTCEPSS rescoreEPSS 7.1% · 94th percentile
  2. 2026-10-21 15:44 UTCEG score recompute
  3. 2026-10-21 15:44 UTCVendor advisory
  4. 2026-10-20 16:33 UTCEPSS rescoreEPSS 7.1% · 94th percentile
  5. 2026-10-20 15:58 UTCEG score recompute
  6. 2026-10-20 15:58 UTCVendor advisory
  7. 2026-10-19 16:32 UTCEPSS rescoreEPSS 7.1% · 94th percentile
  8. 2026-10-19 16:12 UTCEG score recompute
  9. 2026-10-19 16:12 UTCVendor advisory
  10. 2026-10-18 16:32 UTCEPSS rescoreEPSS 7.1% · 94th percentile
  11. 2026-10-18 16:26 UTCVendor advisory
  12. 2026-10-18 05:38 UTCVendor advisory
  13. 2026-10-18 03:34 UTCEG score recompute
  14. 2026-10-17 16:34 UTCEPSS rescoreEPSS 7.1% · 94th percentile
  15. 2026-10-17 05:52 UTCEG score recompute
  16. 2026-10-17 05:52 UTCVendor advisory
  17. 2026-10-16 16:42 UTCEPSS rescoreEPSS 7.1% · 94th percentile
  18. 2026-10-16 06:07 UTCEG score recompute
  19. 2026-10-16 06:07 UTCVendor advisory
  20. 2026-10-15 16:32 UTCEPSS rescoreEPSS 7.1% · 94th percentile
  21. 2026-10-15 06:22 UTCEG score recompute
  22. 2026-10-15 06:22 UTCVendor advisory
  23. 2026-10-14 16:33 UTCEPSS rescoreEPSS 7.1% · 94th percentile
  24. 2026-10-14 06:37 UTCEG score recompute
  25. 2026-10-14 06:37 UTCVendor advisory
Show 75 more
  1. 2026-10-13 16:34 UTCEPSS rescoreEPSS 7.1% · 94th percentile
  2. 2026-10-13 06:51 UTCEG score recompute
  3. 2026-10-13 06:51 UTCVendor advisory
  4. 2026-10-12 16:34 UTCEPSS rescoreEPSS 7.1% · 94th percentile
  5. 2026-10-12 16:00 UTCEG score recompute
  6. 2026-10-12 07:06 UTCVendor advisory
  7. 2026-10-12 03:08 UTCVendor advisory
  8. 2026-10-11 23:09 UTCVendor advisory
  9. 2026-10-11 19:13 UTCEG score recompute
  10. 2026-10-11 19:13 UTCVendor advisory
  11. 2026-10-11 16:58 UTCEG score recompute
  12. 2026-10-11 15:16 UTCVendor advisory
  13. 2026-10-11 14:22 UTCEG score recompute
  14. 2026-10-11 13:49 UTCEPSS rescoreEPSS 7.1% · 94th percentile
  15. 2026-10-11 11:20 UTCEG score recompute
  16. 2026-10-11 11:20 UTCVendor advisory
  17. 2026-10-11 07:23 UTCVendor advisory
  18. 2026-10-11 03:27 UTCVendor advisory
  19. 2026-10-10 23:29 UTCEG score recompute
  20. 2026-10-10 23:29 UTCVendor advisory
  21. 2026-10-10 20:00 UTCEPSS rescoreEPSS 7.1% · 94th percentile
  22. 2026-10-10 19:31 UTCVendor advisory
  23. 2026-10-10 15:34 UTCVendor advisory
  24. 2026-10-10 11:37 UTCVendor advisory
  25. 2026-10-10 07:42 UTCVendor advisory
  26. 2026-10-10 03:46 UTCVendor advisory
  27. 2026-10-09 23:48 UTCEG score recompute
  28. 2026-10-09 23:48 UTCVendor advisory
  29. 2026-10-09 20:07 UTCEPSS rescoreEPSS 7.1% · 94th percentile
  30. 2026-10-09 19:52 UTCVendor advisory
  31. 2026-10-09 15:55 UTCVendor advisory
  32. 2026-10-09 11:58 UTCVendor advisory
  33. 2026-10-09 08:02 UTCVendor advisory
  34. 2026-10-09 04:05 UTCVendor advisory
  35. 2026-10-09 00:08 UTCVendor advisory
  36. 2026-10-08 20:12 UTCEG score recompute
  37. 2026-10-08 20:12 UTCVendor advisory
  38. 2026-10-08 17:12 UTCEPSS rescoreEPSS 7.1% · 94th percentile
  39. 2026-10-08 16:15 UTCVendor advisory
  40. 2026-10-08 12:18 UTCVendor advisory
  41. 2026-10-08 08:22 UTCVendor advisory
  42. 2026-10-08 04:25 UTCVendor advisory
  43. 2026-10-08 00:29 UTCEG score recompute
  44. 2026-10-08 00:29 UTCVendor advisory
  45. 2026-10-07 23:48 UTCEPSS rescoreEPSS 7.1% · 94th percentile
  46. 2026-10-07 20:33 UTCVendor advisory
  47. 2026-10-07 16:37 UTCVendor advisory
  48. 2026-10-07 12:37 UTCVendor advisory
  49. 2026-10-07 08:39 UTCVendor advisory
  50. 2026-10-07 04:43 UTCVendor advisory
  51. 2026-10-07 00:47 UTCVendor advisory
  52. 2026-10-06 20:50 UTCVendor advisory
  53. 2026-10-06 16:52 UTCEG score recompute
  54. 2026-10-06 16:52 UTCVendor advisory
  55. 2026-10-06 15:18 UTCEPSS rescoreEPSS 7.1% · 94th percentile
  56. 2026-10-06 12:56 UTCVendor advisory
  57. 2026-10-06 09:00 UTCVendor advisory
  58. 2026-10-06 05:04 UTCVendor advisory
  59. 2026-10-06 01:06 UTCVendor advisory
  60. 2026-10-05 21:09 UTCEG score recompute
  61. 2026-10-05 21:09 UTCVendor advisory
  62. 2026-10-05 17:43 UTCEPSS rescoreEPSS 7.1% · 94th percentile
  63. 2026-10-05 17:10 UTCVendor advisory
  64. 2026-10-05 13:14 UTCVendor advisory
  65. 2026-10-05 09:16 UTCVendor advisory
  66. 2026-10-05 05:20 UTCVendor advisory
  67. 2026-10-05 01:23 UTCEG score recompute
  68. 2026-10-05 01:23 UTCVendor advisory
  69. 2026-10-04 23:22 UTCEPSS rescoreEPSS 7.1% · 94th percentile
  70. 2026-10-04 21:27 UTCVendor advisory
  71. 2026-10-04 17:31 UTCVendor advisory
  72. 2026-10-04 13:35 UTCVendor advisory
  73. 2026-10-04 09:39 UTCVendor advisory
  74. 2026-10-04 05:41 UTCVendor advisory
  75. 2026-10-04 01:45 UTCVendor advisory

Public detection checks

(2 references)

Public detection checks are referenced for this CVE (1 Nuclei detection template, 1 GitHub checker repository). A detection template checks whether a system is affected; it is not necessarily exploit code. A GitHub repository named or described as a checker or scanner checks whether a system is affected; it is not necessarily exploit code.

  • Nucleihttp/cves/2026/CVE-2026-48710.yaml
    Published Jun 4, 2026

    Starlette - Improper Validation of Unsafe Equivalence in Input

    Open source ↗
  • GitHub checkereris-ths/supply-chain-guard
    Published Apr 1, 2026

    Detect, assess, and respond to supply chain attacks across npm/yarn and Python (pip/poetry/uv). Claude Code skill + standalone scripts. Built during axios RAT (2026-03-31) and Starlette BadHost CVE-2026-48710 (2026-05-22).

    Open source ↗

Frequently asked(6)

What is CVE-2026-48710?
CVE-2026-48710 is a critical-severity vulnerability; its CVE record was published on May 26, 2026. Starlette is a lightweight ASGI framework/toolkit. Prior to version 1.0.1, the HTTP Host request header was not validated before being used to reconstruct request.url. Because the routing algorithm relies on the raw HTTP path while request.url is rebuilt from the Host header, a malformed header…
When was the CVE record for CVE-2026-48710 published?
The CVE record for CVE-2026-48710 was published on May 26, 2026. That is the record's publication date; the vulnerability itself may have been made public earlier. EchelonGraph's copy of the record carries a last-modified date of October 1, 2026; the record at its source may have been updated since.
Is CVE-2026-48710 actively exploited?
Yes. CISA added CVE-2026-48710 to the Known Exploited Vulnerabilities catalog on September 2, 2026, affecting Kludex Starlette. KEV listing indicates confirmed exploitation in the wild; this CVE warrants immediate attention. A fix is available. Apply it.
What is the CVSS score of CVE-2026-48710?
CVE-2026-48710 has a CVSS v3 base score of 6.5 (NVD). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 9.0 (CRITICAL).
Which products are affected by CVE-2026-48710?
CVE-2026-48710 affects Kludex Starlette. The affected packages EchelonGraph has on record, with version ranges, are listed in the Affected Packages section of this page.
How do I remediate CVE-2026-48710?
A fix for CVE-2026-48710 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-48710 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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