CVE-2026-56739

HIGHPre-NVD 8.58.5
EchelonGraph scoreMEDIUM confidence

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

This high-severity CVE scores 8.5 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.3% (22nd percentile of EPSS-scored CVEs). No GitHub Security Advisory CVSS is on record for this CVE.

Triggered by: Headline CVSS from a secondary CVSS source
Sources: EPSS, a secondary CVSS source

Also known asEUVD-2026-86224 (ENISA EUVD)Source: ENISA EUVD

8.5EG
EchelonGraph verdictPlan a fixRemediate within your standard update timelines (the SSVC decision on this page).
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0.3%CVSS: 8.5Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

Logto is the modern, open-source auth infrastructure for SaaS and AI apps. Prior to 1.43.0, Logto fetches administrator-controlled outbound destinations without validating the address used for the connection. Webhook delivery in packages/core/src/libraries/hook/utils.ts can reach special-use and cloud metadata addresses. Custom OAuth2 connectors can use an attacker-selected userInfoEndpoint and forward the OAuth access token in the Authorization header, while OIDC connectors can fetch an attacker-selected jwksUri. The affected operations require tenant administrative configuration access, but they cross the server's network boundary and can expose internal data or upstream provider credentials. This issue is fixed in version 1.43.0.

CVSS v3
8.5
EG Score
8.5HIGHmedium confidence
EG Risk
38
EG Risk 38/100

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)
Severity85% × 45%
Impact severity (EG Severity): CVSS 8.5 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation0.3% × 40%
FIRST EPSS: the 30-day exploitation probability when EchelonGraph scored this CVE.
Automatability0% × 15%
CISA's SSVC Automatable value: no (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at every mission impact level.
Exploitation none (CISA Vulnrichment) · Automatable no (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.
EPSS PROB
0.3%
EPSS %ILE
22nd
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 (8.5): severity, escalated by confirmed exploitation. This CVE's 8.5 is its impact severity (EG Severity), not escalated.

EG Severity
8.5 HIGHCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.a secondary CVSS source · CVSS v3.0 or v3.1
EG Likelihood
0.3% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-29). 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 every mission impact level.CISA BOD 26-04: 60 days if the affected system is publicly exposed; Fix on system upgrade 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 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). 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)60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.

The score's inputs: In CISA KEV no (CISA's KEV catalog) · Automatable no (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

September 24, 2026

Last Modified

September 28, 2026

Advisory Details (4)

Auto-updated Sep 24, 2026
Patch available. Sources: github, github_pr, github_commit, github_release.
GitHub release Patch Available

v1.43.0

Patch available: logto-io/logto v1.43.0

https://github.com/logto-io/logto/releases/tag/v1.43.0
GitHub commit Patch Available

commit 16f4b2e732d5 (logto-io/logto)

Patch available: logto-io/logto v1.43.0 (contains commit 16f4b2e732d5)

https://github.com/logto-io/logto/commit/16f4b2e732d5114ac98646c9370ec6ab61d6ed26
GitHub pull request Patch Available

fix(core,shared): block SSRF in webhook and SSO outbound requests

Patch available: logto-io/logto v1.43.0 (PR #9501 merged 2026-08-27)

https://github.com/logto-io/logto/pull/9501
GitHub advisoryMentions a patch (unverified)

SSRF via Webhooks and Custom OAuth2 Connector UserInfo Endpoint (CWE-918) · Advisory · logto-io/logto · GitHub

https://github.com/logto-io/logto/security/advisories/GHSA-3556-624q-c5w3

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 8× in last 7d / 47× 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.

  1. 2026-11-01 16:34 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  2. 2026-10-31 16:33 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  3. 2026-10-30 16:34 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  4. 2026-10-30 10:32 UTCEG score recompute
  5. 2026-10-29 16:33 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  6. 2026-10-28 16:32 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  7. 2026-10-27 16:32 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  8. 2026-10-26 16:31 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  9. 2026-10-25 16:33 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  10. 2026-10-25 14:18 UTCEG score recompute
  11. 2026-10-24 16:33 UTCEPSS rescoreEPSS 0.3% · 21st percentile
  12. 2026-10-23 18:51 UTCEG score recompute
  13. 2026-10-23 16:32 UTCEPSS rescoreEPSS 0.3% · 21st percentile
  14. 2026-10-22 16:34 UTCEPSS rescoreEPSS 0.3% · 21st percentile
  15. 2026-10-21 16:33 UTCEPSS rescoreEPSS 0.3% · 21st percentile
  16. 2026-10-20 16:33 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  17. 2026-10-19 16:32 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  18. 2026-10-18 16:32 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  19. 2026-10-18 03:29 UTCEG score recompute
  20. 2026-10-17 16:34 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  21. 2026-10-17 02:54 UTCEG score recompute
  22. 2026-10-16 16:42 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  23. 2026-10-15 16:32 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  24. 2026-10-14 16:33 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  25. 2026-10-13 16:34 UTCEPSS rescoreEPSS 0.3% · 20th percentile
Show 43 more
  1. 2026-10-12 16:34 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  2. 2026-10-12 15:54 UTCEG score recompute
  3. 2026-10-11 19:38 UTCEG score recompute
  4. 2026-10-11 16:53 UTCEG score recompute
  5. 2026-10-11 13:53 UTCEG score recompute
  6. 2026-10-11 13:49 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  7. 2026-10-11 02:38 UTCEG score recompute
  8. 2026-10-10 20:00 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  9. 2026-10-10 04:47 UTCEG score recompute
  10. 2026-10-09 20:07 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  11. 2026-10-08 20:15 UTCEG score recompute
  12. 2026-10-08 17:13 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  13. 2026-10-08 09:25 UTCEG score recompute
  14. 2026-10-07 23:48 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  15. 2026-10-07 00:52 UTCEG score recompute
  16. 2026-10-06 15:18 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  17. 2026-10-06 03:04 UTCEG score recompute
  18. 2026-10-05 17:43 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  19. 2026-10-05 05:25 UTCEG score recompute
  20. 2026-10-04 23:22 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  21. 2026-10-03 20:49 UTCEG score recompute
  22. 2026-10-03 14:26 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  23. 2026-10-02 23:08 UTCEG score recompute
  24. 2026-10-02 17:56 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  25. 2026-10-02 01:24 UTCEG score recompute
  26. 2026-10-01 19:50 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  27. 2026-09-30 16:54 UTCEG score recompute
  28. 2026-09-30 15:03 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  29. 2026-09-29 19:14 UTCEG score recompute
  30. 2026-09-29 15:22 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  31. 2026-09-29 08:11 UTCEG score recompute
  32. 2026-09-28 21:18 UTCEG score recompute
  33. 2026-09-28 20:26 UTCEG score recompute
  34. 2026-09-28 18:14 UTCEG score recompute
  35. 2026-09-28 13:51 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  36. 2026-09-27 20:28 UTCEG score recompute
  37. 2026-09-27 13:48 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  38. 2026-09-26 22:47 UTCEG score recompute
  39. 2026-09-26 15:59 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  40. 2026-09-26 01:08 UTCEG score recompute
  41. 2026-09-24 16:34 UTCEG score recompute
  42. 2026-09-24 15:32 UTCEG score recomputeFirst assessed: 8.5 HIGH
  43. 2026-09-24 15:31 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-56739?
CVE-2026-56739 is a high-severity vulnerability; its CVE record was published on September 24, 2026. Logto is the modern, open-source auth infrastructure for SaaS and AI apps. Prior to 1.43.0, Logto fetches administrator-controlled outbound destinations without validating the address used for the connection. Webhook delivery in packages/core/src/libraries/hook/utils.ts can reach special-use and…
When was the CVE record for CVE-2026-56739 published?
The CVE record for CVE-2026-56739 was published on September 24, 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 September 28, 2026; the record at its source may have been updated since.
Is CVE-2026-56739 actively exploited?
CVE-2026-56739 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.3% probability of exploitation in the next 30 days (22nd percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-56739?
CVE-2026-56739 has a CVSS base score of 8.5 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-56739?
A fix for CVE-2026-56739 is available: update to the fixed version the vendor names in its advisory.

Dependency Blast Radius

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