---
id: "CVE-2026-123877"
page: "https://infrastack.ai/live/CVE-2026-123877"
kind: "vulnerability"
aliases: ["CVE-2026-123877"]
title: "Node.js: cached TLS sessions skip stricter certificate checks in https.Agent"
severity: "medium"
cvss: 6.8
epss: null
exploited: false
status: "open"
category: "runtime"
products: []
ecosystems: []
tags: ["https", "node.js", "runtime", "self-hosted", "tls"]
not_affected_if: ["default-config", "single-ca-policy"]
published_at: "2026-11-11T19:17:34+00:00"
first_seen_at: "2026-11-11T19:28:46+00:00"
updated_at: "2026-11-11T19:30:15+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-123877", "first_seen_at": "2026-11-11T19:28:46+00:00"}]
exploit_sources: []
---

# Node.js: cached TLS sessions skip stricter certificate checks in https.Agent

Link for people: https://infrastack.ai/live/CVE-2026-123877 (this .md is for agents)

Node.js https.Agent reuses a cached TLS session across requests that use different certificate authority policies, because the cache key ignores an empty ca array. A later request with a stricter CA policy can therefore send confidential data to a server it should have rejected.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Run `node --version` and compare against the fixed versions below.
- Search your code for `https.Agent` or `ca: []` used alongside requests that rely on the default trust store.

## Timeline

- 2026-11-11T19:28:46+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-123877

## From the sources

A certificate validation bypass in Node.js https.Agent lets a cached TLS session authenticated under one CA policy be reused by a later request with a stricter policy. https.Agent.prototype.getName() assigns the same Agent and session-cache key to a request that omits ca and one that explicitly supplies ca: [], because an omitted value appends nothing to the key while an empty array stringifies to an empty string. The two policies differ: omitting ca uses the default trust store, while supplying ca replaces it. Since they share a key, a TLS session authenticated under the broader default policy is handed to a new connection made under the later ca: [] policy, and TLS 1.3 session resumption carries the earlier authentication forward, so the second request reports authorized === true and transmits confidential data to a server its own CA policy would reject on a fresh connection. This vulnerability affects Node.js 26.x, 24.x, and 22.x.

---

_Free to read, with fair use of about 60 pages a minute. For higher limits or API access: sales@infrastack.ai_