CVE-2026-55787

HIGHPre-NVD 7.17.1
EchelonGraph scoreMEDIUM confidence

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

This high-severity CVE scores 7.1 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.3% (21st 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
Elevated

Also known asEUVD-2026-101588 (ENISA EUVD) · GHSA-794r-5rp2-fpg8 (GitHub Security Advisories)Source: ENISA EUVD

7.1EG
EchelonGraph verdictPlan a fixRemediate within your standard update timelines (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: 0.3%CVSS: 7.1Exploit: No code on recordExposed services: Not assessed

A fix is available — apply it.

Flyto2 Core is an execution kernel for automation and AI-agent workflows. Prior to 2.26.3, validate_url_ssrf and is_private_ip in src/core/utils.py compare resolved addresses only against native private IPv4 and IPv6 ranges and do not unwrap IPv4-mapped, IPv4-compatible, 6to4, or NAT64 transition addresses. An authenticated workflow author can provide a transition-form literal URL through the Execution API POST /v1/execute route, http.get, or sibling guarded outbound-request modules, causing the guard to accept an address whose embedded IPv4 points to loopback, RFC 1918, or cloud metadata services. On a host that routes the selected transition form, the outbound request reaches the internal destination and returns the response body to the workflow caller, enabling read SSRF and disclosure of internal-service data or cloud credentials. This issue is fixed in version 2.26.3.

CVSS v3
7.1
EG Score
7.1HIGHmedium confidence
EG Risk
48
EG Risk 48/100

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)
Severity71% × 45%
Impact severity (EG Severity): CVSS 7.1 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.
Automatability0% × 15%
CISA's SSVC Automatable value: no (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at low or medium mission impact; Track* at high (mission-essential systems).
Exploitation public PoC (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
21st
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 (7.1): severity, escalated by confirmed exploitation. This CVE's 7.1 is its impact severity (EG Severity), not escalated.

EG Severity
7.1 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. 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; Track* at high (mission-essential systems).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: the SSVC and BOD 26-04 blocks below.

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

A fix is available. Apply it within your standard update timelines.

Exploitation public PoC (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.

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

July 6, 2026

Last Modified

October 16, 2026

Advisory Details (4)

Auto-updated Oct 14, 2026
Patch available. Sources: github, github_pr, github_commit, github_release.
GitHub release Patch Available

v2.26.3 — SSRF IPv6-transition guard fix (GHSA-794r-5rp2-fpg8)

Patch available: flytohub/flyto-core v2.26.3

https://github.com/flytohub/flyto-core/releases/tag/v2.26.3
GitHub commit Patch Available

commit 519e040384a7 (flytohub/flyto-core)

Patch available: flytohub/flyto-core v2.26.3 (contains commit 519e040384a7)

https://github.com/flytohub/flyto-core/commit/519e040384a74984848c4e84a6600e5f1020a6d2
GitHub pull request Patch Available

security: fix SSRF guard bypass via IPv6 transition addresses (GHSA-794r-5rp2-fpg8)

Patch available: flytohub/flyto-core v2.26.3 (PR #20 merged 2026-05-30)

https://github.com/flytohub/flyto-core/pull/20
GitHub advisoryMentions a patch (unverified)

SSRF guard bypass via IPv6 transition addresses (IPv4-mapped / 6to4 / NAT64) in validate_url_ssrf · Advisory · flytohub/flyto-core · GitHub

https://github.com/flytohub/flyto-core/security/advisories/GHSA-794r-5rp2-fpg8

Vendor Advisories for CVE-2026-55787(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)
PyPI(1)
PackageVulnerable rangeFix by version rangeDependents
flyto-core1.0.0 ... 2.9.0 (213 versions)
  • every version up to 2.26.3: fixed in 2.26.3
—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 9× in last 7d / 24× 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. 2026-10-27 16:32 UTCEPSS rescoreEPSS 0.3% · 21st percentile
  2. 2026-10-26 16:31 UTCEPSS rescoreEPSS 0.3% · 21st percentile
  3. 2026-10-25 16:33 UTCEPSS rescoreEPSS 0.3% · 21st percentile
  4. 2026-10-25 14:18 UTCEG score recompute
  5. 2026-10-24 16:33 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  6. 2026-10-24 02:45 UTCEG score recompute
  7. 2026-10-23 16:32 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  8. 2026-10-22 16:34 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  9. 2026-10-21 16:33 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  10. 2026-10-20 16:33 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  11. 2026-10-19 16:32 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  12. 2026-10-18 16:32 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  13. 2026-10-18 03:30 UTCEG score recompute
  14. 2026-10-17 16:34 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  15. 2026-10-16 20:10 UTCEG score recompute
  16. 2026-10-16 16:42 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  17. 2026-10-15 16:32 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  18. 2026-10-15 15:26 UTCEG score recompute
  19. 2026-10-15 15:07 UTCEG score recompute
  20. 2026-10-14 19:32 UTCEG score recompute
  21. 2026-10-12 15:55 UTCEG score recompute
  22. 2026-10-11 19:38 UTCEG score recompute
  23. 2026-10-11 16:53 UTCEG score recompute
  24. 2026-10-11 14:16 UTCEG score recompute
  25. 2026-07-30 10:30 UTCEG score recompute
Show 3 more
  1. 2026-07-26 12:47 UTCEG score recompute
  2. 2026-07-23 03:20 UTCEG score recompute
  3. 2026-07-06 18:22 UTCEG score recompute

Related CVEs(same product + same CWE)

Frequently asked(5)

What is CVE-2026-55787?
CVE-2026-55787 is a high-severity vulnerability; its CVE record was published on July 6, 2026. Flyto2 Core is an execution kernel for automation and AI-agent workflows. Prior to 2.26.3, validateurlssrf and isprivateip in src/core/utils.py compare resolved addresses only against native private IPv4 and IPv6 ranges and do not unwrap IPv4-mapped, IPv4-compatible, 6to4, or NAT64 transition…
When was the CVE record for CVE-2026-55787 published?
The CVE record for CVE-2026-55787 was published on July 6, 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 16, 2026; the record at its source may have been updated since.
Is CVE-2026-55787 actively exploited?
CVE-2026-55787 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.3% probability of exploitation in the next 30 days (21st percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-55787?
CVE-2026-55787 has a CVSS base score of 7.1 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-55787?
A fix for CVE-2026-55787 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-55787 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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