macOS: `tls.getCACertificates('system')` uses revocation-enabled trust policy, causing 5-10s startup on machines with network filters

Version

v24.15.0 (also v25 per anthropics/claude-code#53660 measurements)

Platform

Darwin (macOS 26.4.1, Apple Silicon Mac16,12). Reproduces on macOS Sonoma/Sequoia per the linked downstream reports.

Subsystem

tls, crypto

What steps will reproduce the bug?

On a Mac with any active network-flow filter (corporate NetworkExtension, content filter, or even a userland VPN-style daemon like ZeroTier), and a moderately-sized login keychain:

$ node -e 'const t0=process.hrtime.bigint();
           const c = require("tls").getCACertificates("system");
           console.log(`returned=${c.length} elapsed=${(Number(process.hrtime.bigint()-t0)/1e6).toFixed(0)}ms`)'
returned=34 elapsed=5287ms

The same call against "bundled" returns in ~0.1ms. HTTPS request times via --use-system-ca are ~100× slower than --use-bundled-ca (5093ms vs 103ms to api.github.com).

The bug is in node::crypto::ReadMacOSKeychainCertificates (src/crypto/crypto_x509.cc / wherever the macOS branch lives). It calls SecTrustEvaluateWithError with a revocation-enabled policy when collecting trust anchors, which causes trustd to attempt AIA/OCSP/CRL fetches for every cert. When a NetworkExtension content filter is present, each flow goes through per-flow cryptographic signing (~1-2ms × hundreds of certs = 5-10 seconds total) before being denied. Without a flow filter the cost is smaller but still present.

How often does it reproduce?

Every invocation. Stable across reboots and Node versions in the v24.x / v25 line.

What is the expected behavior? Why is that the expected behavior?

tls.getCACertificates("system") should be fast (single-digit milliseconds for a typical keychain) because it's collecting trust anchors, not validating a server chain. Revocation checks are pointless during anchor collection — a trust anchor's revocation status is determined by user/admin trust settings, not by an OCSP responder.

What do you see instead?

5-10+ seconds of latency, predominantly in synchronous XPC round-trips to trustd. Effectively blocks Node CLI startup any time the CLI's CA loader touches the system store. Several Node-based CLIs are affected in practice:

• anthropics/claude-code#53660 — comprehensive root-cause analysis. Their measurement on a corporate Mac: 9.7s for 18 certs (530ms/cert), vs 0.3ms/cert for direct C calls using SecPolicyCreateBasicX509. They shipped a CLAUDE_CODE_CERT_STORE=bundled env var workaround.
• github/copilot-cli#3330 (filing concurrently) — same call costs 5+ seconds on every copilot invocation. The CLI's code explicitly asks for "system" certs in addition to "bundled".
• github/copilot-cli#1250 — Windows variant of the same call (different failure mode, same offending line).

Additional information

Proposed fix

Per the anthropics/claude-code#53660 analysis, the call should use SecPolicyCreateBasicX509() (no revocation) when enumerating system CAs to use as trust anchors. Alternatively, the function could skip trust evaluation entirely and call SecTrustSettingsCopyCertificates(kSecTrustSettingsDomainAdmin/System) to collect anchors without validation. Either approach removes revocation from the hot startup path.

Reproducer kit

# Standalone measurement
node -e 'const t0=process.hrtime.bigint();
         require("tls").getCACertificates("system");
         console.log(`${(Number(process.hrtime.bigint()-t0)/1e6).toFixed(0)}ms`)'

# HTTPS A/B
node --use-bundled-ca -e 'require("https").get("https://api.github.com/zen",r=>r.on("data",()=>{}).on("end",()=>{}))'   # ~100ms
node --use-system-ca  -e 'require("https").get("https://api.github.com/zen",r=>r.on("data",()=>{}).on("end",()=>{}))'   # ~5s

# Sample to confirm the syscall pattern
node --use-system-ca -e 'require("tls").getCACertificates("system")' &
PID=$!; sleep 0.1; sample $PID 3 -mayDie

Sample output during the wait deterministically shows:

node::crypto::ReadMacOSKeychainCertificates
  → node::crypto::IsCertificateTrustedForPolicy
    → SecTrustEvaluateWithError
      → securityd_send_sync_and_do (XPC to trustd)

Why this matters beyond corporate networks

Anthropic's analysis (and the original v24 design assumption) treats this as a "corporate Macs only" problem. In practice, any userland flow-handling daemon — ZeroTier, Tailscale, Cloudflare WARP, certain VPN clients — places similar code in the path. The fix doesn't depend on detecting the filter; it's simply correct to skip revocation when enumerating trust anchors.

Related Node-side tracking

• #58990 — tracking issue for custom CA support; lists "Load system CA certificates off thread" as done, but off-thread loading doesn't fix the cost, only moves it. The root cause is the revocation policy.
• #57163 — --use-system-ca intermediate-cert issues on Windows.
• #58346 — request for env-var alternative to --use-system-ca.

Start in src/crypto/crypto_x509.cc at node::crypto::ReadMacOSKeychainCertificates and trace its trust-policy evaluation. Run the provided tls.getCACertificates("system") timing reproducer on macOS, then verify that system CA collection avoids the revocation-related trustd delay while preserving the returned certificates and HTTPS behavior.