# SC-073: CAs must reject compromised and weak keys

> SC-073 tells CAs to reject certificate requests for keys already reported compromised and for known weak keys (Debian, ROCA, close primes) from November 2024.

Source: https://ssl.sh/ballots/sc-073/
Last updated: 2026-11-10

SC-073 makes CAs refuse to certify keys that are known to be unsafe. If a [private key](https://ssl.sh/glossary/private-key/) has been reported compromised to the CA, or belongs to a known class of weak keys, the CA must reject the certificate request; the ballot set 2024-11-15 as the date these rules apply.

## What changed

SC-073 reworked §6.1.1.3 of the [Baseline Requirements](https://ssl.sh/glossary/baseline-requirements/) to cover two kinds of unsafe keys. Compromised keys: a CA learns about them through its normal revocation-request channels, and once notified it must not issue a new certificate for that key. Weak keys: CAs must reject at least the Debian weak keys (from the 2008 Debian OpenSSL random number bug) listed in a repository maintained under the CA/B Forum's GitHub, keys detected by the ROCA tools (the 2017 Infineon RSA flaw), and RSA keys whose primes are so close that Fermat factorization breaks them within 100 rounds. The ballot builds on SSL.com's earlier SC-059v2 "weak key guidance", which had failed.

## Effective dates

The BR change took effect on 2024-07-01; the ballot text states the new §6.1.1.3 rules become effective on 2024-11-15.

## Who is affected

Anyone who reuses an old key pair: after a key-compromise report, or with keys generated by flawed hardware or software, renewal will be refused. Normal keys from current OpenSSL or ACME clients pass without issue.

## What to do

Generate a fresh key for each certificate, or at least after any suspicion of leakage; most ACME clients do this by default. Never reuse a key you have reported as compromised. To confirm which key a certificate uses, compare them with the [key matcher](https://ssl.sh/tools/key-matcher/).


| Field | Value |
|---|---|
| Ballot | SC-073 |
| Status | Passed |
| Adopted | 2024-05-03 |
| Effective | 2024-07-01 |
| BR version | 2.0.5 |
| Official page | https://cabforum.org/2024/06/07/ballot-sc073-compromised-and-weak-keys/ |