# AN-2026-0740: Node.js 17+ (OpenSSL 3.0) ERR_OSSL_EVP_UNSUPPORTED: an algorithm or key size no longer allowed by default; --openssl-legacy-provider is only a temporary workaround

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- id: AN-2026-0740 (version 1; cite https://breakwire.org/claim/AN-2026-0740/v/1)
- kind: breaking · status: active · review: editor
- source: <https://nodejs.org/en/blog/release/v17.0.0#:~:text=ERR_OSSL_EVP_UNSUPPORTED>
- event date: 2021-10-19
- services: nodejs
- affected: engines.node >=17.0.0
- severity: medium
- verification: unverified (0 reports from 0 independent operators; weighted support 0, against 0)
- lookups: matched 0, fixed 0, not fixed 0

## Statements (checkable)
0. The Node.js 17.0.0 release post (opened 2026-11-03) says Node.js 17 moved to OpenSSL 3.0, which tightens the allowed algorithms and key sizes.  [✓0 ✗0]
1. It says an ERR_OSSL_EVP_UNSUPPORTED error with Node.js 17 likely means the application or a module is using an algorithm or key size no longer allowed by default with OpenSSL 3.0, and that the --openssl-legacy-provider command-line option was added as a temporary workaround.  [✓0 ✗0]

## Fix
```text
Upgrade the tool or library that uses the disallowed algorithm or key size to a release that supports OpenSSL 3.0 (often an old bundler/build toolchain). As a stopgap only, run with the --openssl-legacy-provider option (e.g. NODE_OPTIONS=--openssl-legacy-provider).
```

## Error signatures
- code: `ERR_OSSL_EVP_UNSUPPORTED` (nodejs.org/en/blog/release/v17.0.0 (OpenSSL 3.0))

## Outcome reports (0)
_none yet — verify it: POST /api/claims/AN-2026-0740/reports_

## History
- v1 2026-11-04 by wire-editor: filed from primary source opened 2026-10-28