On Fri, 28 Aug 2026 13:30:33 -0400 Andy Newton <[email protected]> wrote: > This was brought to my attention this morning, and I thought it might > be interesting to this group. > > https://infosec.exchange/@badkeys/117166365236396478
For what it's worth: badkeys is my project, I've done scans of DKIM keys for known vulnerabilities. Happy to answer questions here or directly. Copying over the mastodon post: "I've recently scanned DKIM keys for vulnerabilities, more extensively than previous scans. DKIM keys with the Debian OpenSSL bug are still very common. So are too-short RSA keys (quite a few 512 and even 384 bit keys, and *many* 768 bit, which is still difficult to break, but possible). Also, a notable number publish a private key in their DKIM record. (This is only a problem if they actually use the same key elsewhere correctly.) I tried disclosing things, but manual disclosure impractical for thousands of affected hosts and automated disclosure is difficult (plenty without security.txt, security@ often is rejected). Replies to disclosures also show a common misunderstanding: People believe they are unaffected saying these keys are old and unused. This shows a fundamental confusion about how digital signatures work. Attackers don't care if you use insecure keys as long as they can use them. Some stats for the latest scan: https://monitor.badkeys.info/dkim/2026-08-11-dkim-badkeys.html " And previously: https://16years.secvuln.info/ -- Hanno Böck - Independent security researcher https://itsec.hboeck.de/ https://badkeys.info/ _______________________________________________ Ietf-dkim mailing list -- [email protected] To unsubscribe send an email to [email protected]
