CVE-2026-103262

HIGHPre-NVD 7.57.5
EchelonGraph scoreMEDIUM confidence

“—” beside the score: it is equal to the CVSS score beside it.

Score 7.5 from GitHub Security Advisory (severity: HIGH) published 2026-10-01. A secondary CVSS source baseline 7.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: EPSS, GitHub Security Advisory, a secondary CVSS source
Trending — Patch released this weekElevated

Also known asEUVD-2026-90656 (ENISA EUVD) · GHSA-h36x-fm6v-f9vx (GitHub Security Advisories)Source: ENISA EUVD

7.5EG
EchelonGraph verdictPlan a fixRemediate within your standard update timelines at low or medium mission impact and sooner than that at high (the SSVC decision on this page).
  • CISA's Vulnrichment rates exploitation as PoC; EchelonGraph holds no exploit-code reference for it
CISA-KEV: Not listedEPSS PROB: 0.6%CVSS: 7.5Exploit: No code on recordExposed services: Not assessed

A fix is available — apply it.

Tornado versions before 6.5.9 contain an unbounded memory accumulation vulnerability in CurlAsyncHTTPClient that allows remote attackers to cause denial of service by sending a compressed response. Attackers can send a gzip-encoded decompression bomb that accumulates in memory without size limits, causing the application process to be killed by out-of-memory conditions.

CVSS v3
7.5
EG Score
7.5HIGHmedium confidence
EG Risk
65
EG Risk 65/100

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)
Severity75% × 45%
Impact severity (EG Severity): CVSS 7.5 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation40% × 40%
EchelonGraph's fixed weight for EG-KEV Tier 3 (Elevated): a constant, not a probability.
Automatability100% × 15%
CISA's SSVC Automatable value: yes (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at low or medium mission impact; Attend at high (mission-essential systems).
Exploitation public PoC (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 within your standard update timelines at low or medium mission impact and sooner than that at high.
EPSS PROB
0.6%
EPSS %ILE
50th
KEV
Not listed

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

The EG score (7.5): severity, escalated by confirmed exploitation. This CVE's 7.5 is its impact severity (EG Severity), not escalated.

EG Severity
7.5 HIGHCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
EG Likelihood
0.6% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-30). FIRST's exploitation probability, not an EchelonGraph model.
Confirmed exploitation
None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
EG Priority
SSVC Track at medium mission impactTrack at low or medium mission impact; Attend at high (mission-essential systems).CISA BOD 26-04: 14 days if the affected system is publicly exposed; 60 days if it is not.Each input and its source, and whom BOD 26-04 binds: the SSVC and BOD 26-04 blocks below.

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

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

Exploitation public PoC (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)14 days if the affected system is publicly exposed; 60 days if it is not.

The score's inputs: In CISA KEV no (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

Published

October 1, 2026

Last Modified

October 6, 2026

Advisory Details (3)

Auto-updated Oct 1, 2026
Patch available. Sources: github, github_commit.
Web page

Tornado before 6.5.9 Denial of Service via CurlAsyncHTTPClient | Advisories | VulnCheck

https://www.vulncheck.com/advisories/tornado-before-6.5.9-denial-of-service-via-curlasynchttpclient
GitHub commit

commit e412435febba (tornadoweb/tornado)

Fix landed in tornadoweb/tornado commit e412435febba — awaiting tagged release

https://github.com/tornadoweb/tornado/commit/e412435febba4569c552c5c9054f1bf92bd171a9
GitHub advisoryMentions a patch (unverified)

tornado: CurlAsyncHTTPClient enforces no response-size limit — decompression bomb drives unbounded memory accumulation to OOM (CWE-400, CWE-409) · Advisory · tornadoweb/tornado · GitHub

https://github.com/tornadoweb/tornado/security/advisories/GHSA-chx6-46f5-w4vp

Patch Availability(10)

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

(4 across 4 ecosystems)
Debian:12(1)
PackageVulnerable rangeFix by version rangeDependents
python-tornado6.2.0-3 ... 6.5.5-5 (24 versions)
  • every version on: no fix on record
—
Debian:13(1)
PackageVulnerable rangeFix by version rangeDependents
python-tornado6.4.2-3 ... 6.5.5-5 (13 versions)
  • every version on: no fix on record
—
Debian:14(1)
PackageVulnerable rangeFix by version rangeDependents
python-tornado6.4.2-3 ... 6.5.5-5 (11 versions)
  • every version on: no fix on record
—
PyPI(1)
PackageVulnerable rangeFix by version rangeDependents
tornado0.2 ... 6.5b1 (84 versions)
  • every version up to 6.5.9: fixed in 6.5.9
—

Weakness Classification(1)

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

Additional Vendor Advisories

(2)

Vendors that published advisories for this CVE beyond the curated set above. Broader coverage but minimal per-row detail — click through for the original advisory.

Data Freshness Timeline

(refreshed 13× in last 7d / 78× 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.

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. 1 repeat row among the latest 87 is merged into the row it repeats.

  1. 2026-11-01 16:33 UTCEPSS rescoreEPSS 0.6% · 50th percentile
  2. 2026-10-31 16:31 UTCEPSS rescoreEPSS 0.6% · 50th percentile
  3. 2026-10-31 12:33 UTCEG score recompute
  4. 2026-10-31 12:33 UTCVendor advisory
  5. 2026-10-31 12:33 UTCGHSA enrichmentGHSA-h36x-fm6v-f9vx · GitHub severity HIGH · GitHub CVSS 7.5
  6. 2026-10-30 16:33 UTCEPSS rescoreEPSS 0.6% · 50th percentile
  7. 2026-10-29 16:32 UTCEPSS rescoreEPSS 0.6% · 50th percentile
  8. 2026-10-28 16:31 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  9. 2026-10-27 19:45 UTCEG score recompute
  10. 2026-10-27 19:45 UTCVendor advisory
  11. 2026-10-27 19:45 UTCGHSA enrichmentGHSA-h36x-fm6v-f9vx · GitHub severity HIGH · GitHub CVSS 7.5
  12. 2026-10-27 16:31 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  13. 2026-10-26 16:30 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  14. 2026-10-25 16:32 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  15. 2026-10-25 14:56 UTCEG score recompute
  16. 2026-10-24 16:31 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  17. 2026-10-23 16:31 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  18. 2026-10-22 16:33 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  19. 2026-10-21 16:31 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  20. 2026-10-20 19:15 UTCEG score recompute
  21. 2026-10-20 19:15 UTCVendor advisory
  22. 2026-10-20 19:15 UTCGHSA enrichmentGHSA-h36x-fm6v-f9vx · GitHub severity HIGH · GitHub CVSS 7.5
  23. 2026-10-20 16:31 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  24. 2026-10-19 16:31 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  25. 2026-10-18 16:31 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
Show 61 more
  1. 2026-10-18 05:09 UTCEG score recompute
  2. 2026-10-17 19:45 UTCEG score recompute
  3. 2026-10-17 19:45 UTCVendor advisory
  4. 2026-10-17 19:45 UTCGHSA enrichmentGHSA-h36x-fm6v-f9vx · GitHub severity HIGH · GitHub CVSS 7.5
  5. 2026-10-17 16:33 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  6. 2026-10-16 16:40 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  7. 2026-10-15 16:31 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  8. 2026-10-14 16:31 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  9. 2026-10-13 16:33 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  10. 2026-10-12 16:40 UTCEG score recompute
  11. 2026-10-12 16:33 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  12. 2026-10-12 01:49 UTCGHSA enrichmentGHSA-h36x-fm6v-f9vx · GitHub severity HIGH · GitHub CVSS 7.5
  13. 2026-10-11 20:15 UTCEG score recompute
  14. 2026-10-11 18:28 UTCEG score recompute
  15. 2026-10-11 15:01 UTCEG score recompute
  16. 2026-10-11 13:47 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  17. 2026-10-11 12:52 UTCEG score recompute
  18. 2026-10-11 12:52 UTCGHSA enrichmentGHSA-h36x-fm6v-f9vx · GitHub severity HIGH · GitHub CVSS 7.5
  19. 2026-10-10 23:39 UTCEG score recompute
  20. 2026-10-10 23:39 UTCGHSA enrichmentGHSA-h36x-fm6v-f9vx · GitHub severity HIGH · GitHub CVSS 7.5
  21. 2026-10-10 19:59 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  22. 2026-10-10 10:42 UTCGHSA enrichmentGHSA-h36x-fm6v-f9vx · GitHub severity HIGH · GitHub CVSS 7.5
  23. 2026-10-09 21:45 UTCEG score recompute
  24. 2026-10-09 21:44 UTCGHSA enrichmentGHSA-h36x-fm6v-f9vx · GitHub severity HIGH · GitHub CVSS 7.5
  25. 2026-10-09 20:06 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  26. 2026-10-09 08:48 UTCGHSA enrichmentGHSA-h36x-fm6v-f9vx · GitHub severity HIGH · GitHub CVSS 7.5
  27. 2026-10-08 19:45 UTCEG score recompute
  28. 2026-10-08 19:45 UTCGHSA enrichmentGHSA-h36x-fm6v-f9vx · GitHub severity HIGH · GitHub CVSS 7.5
  29. 2026-10-08 17:11 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  30. 2026-10-08 06:25 UTCEG score recompute
  31. 2026-10-08 06:25 UTCGHSA enrichmentGHSA-h36x-fm6v-f9vx · GitHub severity HIGH · GitHub CVSS 7.5
  32. 2026-10-07 23:47 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  33. 2026-10-07 17:27 UTCGHSA enrichmentGHSA-h36x-fm6v-f9vx · GitHub severity HIGH · GitHub CVSS 7.5
  34. 2026-10-07 03:35 UTCEG score recompute
  35. 2026-10-07 03:34 UTCGHSA enrichmentGHSA-h36x-fm6v-f9vx · GitHub severity HIGH · GitHub CVSS 7.5
  36. 2026-10-06 15:17 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  37. 2026-10-06 14:33 UTCGHSA enrichmentGHSA-h36x-fm6v-f9vx · GitHub severity HIGH · GitHub CVSS 7.5
  38. 2026-10-06 01:33 UTCGHSA enrichmentGHSA-h36x-fm6v-f9vx · GitHub severity HIGH · GitHub CVSS 7.5
  39. 2026-10-06 01:32 UTCEG score recompute
  40. 2026-10-06 01:32 UTCGHSA enrichmentGHSA-h36x-fm6v-f9vx · GitHub severity HIGH · GitHub CVSS 7.5
  41. 2026-10-06 00:41 UTCEG score recompute
  42. 2026-10-06 00:41 UTCGHSA enrichmentGHSA-h36x-fm6v-f9vx · GitHub severity HIGH · GitHub CVSS 7.5
  43. 2026-10-05 19:05 UTCEG score recompute
  44. 2026-10-05 19:05 UTCGHSA enrichmentGHSA-h36x-fm6v-f9vx · GitHub severity HIGH · GitHub CVSS 7.5
  45. 2026-10-05 17:42 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  46. 2026-10-05 06:08 UTCEG score recompute
  47. 2026-10-05 06:08 UTCGHSA enrichmentGHSA-h36x-fm6v-f9vx · GitHub severity HIGH · GitHub CVSS 7.5
  48. 2026-10-04 23:21 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  49. 2026-10-04 17:11 UTCGHSA enrichmentGHSA-h36x-fm6v-f9vx · GitHub severity HIGH · GitHub CVSS 7.5
  50. 2026-10-04 04:11 UTCGHSA enrichmentGHSA-h36x-fm6v-f9vx · GitHub severity HIGH · GitHub CVSS 7.5
  51. 2026-10-03 15:15 UTCEG score recompute
  52. 2026-10-03 15:14 UTCGHSA enrichmentGHSA-h36x-fm6v-f9vx · GitHub severity HIGH · GitHub CVSS 7.5
  53. 2026-10-03 14:25 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  54. 2026-10-03 02:18 UTCEG score recompute
  55. 2026-10-03 02:17 UTCGHSA enrichmentGHSA-h36x-fm6v-f9vx · GitHub severity HIGH · GitHub CVSS 7.5
  56. 2026-10-02 13:20 UTCGHSA enrichmentGHSA-h36x-fm6v-f9vx · GitHub severity HIGH · GitHub CVSS 7.5
  57. 2026-10-02 00:23 UTCEG score recompute
  58. 2026-10-02 00:23 UTCGHSA enrichmentGHSA-h36x-fm6v-f9vx · GitHub severity HIGH · GitHub CVSS 7.5
  59. 2026-10-01 11:27 UTCEG score recompute
  60. 2026-10-01 10:51 UTCEG score recomputeFirst assessed: 7.5 HIGH
  61. 2026-10-01 10:50 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-103262?
CVE-2026-103262 is a high-severity vulnerability; its CVE record was published on October 1, 2026. Tornado versions before 6.5.9 contain an unbounded memory accumulation vulnerability in CurlAsyncHTTPClient that allows remote attackers to cause denial of service by sending a compressed response. Attackers can send a gzip-encoded decompression bomb that accumulates in memory without size limits,…
When was CVE-2026-103262 made public?
CVE-2026-103262 was made public on September 14, 2026: that is the date its CVE record's CNA, VulnCheck, gives for when the vulnerability was made public. The CVE record itself was published on October 1, 2026. EchelonGraph's copy of the record carries a last-modified date of October 6, 2026; the record at its source may have been updated since.
Is CVE-2026-103262 actively exploited?
CVE-2026-103262 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.6% probability of exploitation in the next 30 days (50th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-103262?
CVE-2026-103262 has a CVSS base score of 7.5 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-103262?
A fix for CVE-2026-103262 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-103262 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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