CVE-2026-84961

HIGHPre-NVD 7.47.4—
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 7.4 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.1%, top 96% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, secondary
Trending — Patch released this week
7.4EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 7.4Exploit: None knownExposed: 0

A fix is available — apply it.

undici's BalancedPool constructor passes its entire options object through an internal deep-clone that serializes and reparses the value as JSON. Because JSON cannot represent functions, any function-valued TLS option, such as a caller-supplied checkServerIdentity callback or a custom connector inside the connect option, is silently discarded before it reaches the TLS layer. As a result a peer whose certificate the application's custom checkServerIdentity was written to reject, but which still passes Node's default hostname and chain checks, is accepted when reached through BalancedPool. The Client, Pool, and Agent dispatchers are not affected because they extract the connect and tls options before cloning. This affects undici versions from 7.24.1 up to 7.29.1 and from 8.0.0 up to 8.10.2, and only when the application supplies a function-valued connect or tls option to BalancedPool. Users should upgrade to undici 7.29.1 or 8.10.2.

CVSS v3
7.4
EG Score
7.4(medium)
EG Risk
33(Track)
EG Risk 33/100SSVC: 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
Severity74% × 45%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
4%
KEV
Not listed

Published

September 4, 2026

Last Modified

September 8, 2026

Advisory Details (2)

Auto-updated Sep 4, 2026
Patch available. Sources: github.
generic

Security Advisories | OpenJS Foundation CVE Numbering Authority

https://cna.openjsf.org/security-advisories.html
github Patch Available

undici vulnerable to TLS certificate validation bypass via dropped connect options in BalancedPool · Advisory · nodejs/undici · GitHub

https://github.com/nodejs/undici/security/advisories/GHSA-w293-vg96-wgc3

Vendor Advisories for CVE-2026-84961(2)

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

Patch Availability(1)

Vendor / EcosystemFixed in / PatchReleasedSource
redhatgrafana12-4-main-12.4.10-0.2.hum12026-09-09redhat

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

(3 across 3 ecosystems)
Debian:12(1)
PackageVulnerable rangeFixed inDependents
node-undici5.15.0+dfsg1+~cs20.10.9.3-1 ... 8.9.0+dfsg+~cs3.2.0-1 (39 versions)——
Debian:13(1)
PackageVulnerable rangeFixed inDependents
node-undici7.15.0+dfsg+~cs3.2.0-1 ... 8.9.0+dfsg+~cs3.2.0-1 (15 versions)——
Debian:14(1)
PackageVulnerable rangeFixed inDependents
node-undici7.15.0+dfsg+~cs3.2.0-1 ... 8.9.0+dfsg+~cs3.2.0-1 (15 versions)——

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 13× in last 7d / 18× 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. 2026-09-11 14:53 UTCEPSS rescore
  2. 2026-09-11 14:53 UTCEPSS rescore
  3. 2026-09-11 13:46 UTCEG score recompute
  4. 2026-09-11 13:46 UTCVendor advisory
  5. 2026-09-11 02:47 UTCVendor advisory
  6. 2026-09-10 15:49 UTCEG score recompute
  7. 2026-09-10 15:49 UTCVendor advisory
  8. 2026-09-10 04:51 UTCVendor advisory
  9. 2026-09-08 01:35 UTCEG score recompute
  10. 2026-09-06 15:13 UTCEG score recompute
  11. 2026-09-06 13:48 UTCEPSS rescore
  12. 2026-09-05 17:16 UTCEG score recompute
  13. 2026-09-05 15:31 UTCEPSS rescore
  14. 2026-09-04 19:19 UTCEG score recompute
  15. 2026-09-04 18:49 UTCEG score recompute
  16. 2026-09-04 17:26 UTCEG score recompute
  17. 2026-09-04 16:55 UTCEG score recompute
  18. 2026-09-04 16:54 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-84961?
CVE-2026-84961 is a high vulnerability published on September 4, 2026. undici's BalancedPool constructor passes its entire options object through an internal deep-clone that serializes and reparses the value as JSON. Because JSON cannot represent functions, any function-valued TLS option, such as a caller-supplied checkServerIdentity callback or a custom connector…
When was CVE-2026-84961 disclosed?
CVE-2026-84961 was first published in the National Vulnerability Database on September 4, 2026, with the most recent update on September 8, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-84961 actively exploited?
CVE-2026-84961 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 95.9% of all scored CVEs.
What is the CVSS score of CVE-2026-84961?
CVE-2026-84961 has a CVSS v3 base score of 7.4 (NVD).
How do I remediate CVE-2026-84961?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-84961, 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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