--- title: OpenSSH: Release Notes | daily.dev description: OpenSSH release notes covering versions 9.9 through 10.4. Key highlights include: OpenSSH 10.4 adds experimental post-quantum composite signature scheme... canonical: https://daily.dev/posts/openssh-release-notes-iatm6rseu twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: OpenSSH: Release Notes | daily.dev og:description: OpenSSH release notes covering versions 9.9 through 10.4. Key highlights include: OpenSSH 10.4 adds experimental post-quantum composite signature scheme... og:url: https://daily.dev/posts/openssh-release-notes-iatm6rseu og:image: https://api.daily.dev/og/posts/IATM6RsEU.png og:image:alt: OpenSSH: Release Notes og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # OpenSSH: Release Notes **[Lobsters](https://daily.dev/sources/lobsters)** · 387 min read · 2 upvotes · 0 comments ## Summary OpenSSH release notes covering versions 9.9 through 10.4. Key highlights include: OpenSSH 10.4 adds experimental post-quantum composite signature scheme (ML-DSA 44 + Ed25519), fixes multiple security issues including malicious server path traversal in sftp/scp, a pre-auth DoS with GSSAPI, and a client-side use-after-free. OpenSSH 10.0 was a major release removing DSA support, splitting sshd into separate sshd-auth and sshd-session binaries, disabling finite-field Diffie-Hellman by default, and making ML-KEM768x25519 the default key exchange. Earlier releases addressed CVE-2025-26465 (MITM via VerifyHostKeyDNS) and CVE-2025-26466 (memory/CPU DoS via SSH2_MSG_PING). Across releases, there are numerous bugfixes, portability improvements, and incremental security hardening measures. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### What changed in OpenSSH 10.4? OpenSSH 10.4, released July 6, 2026, fixes several security issues including a malicious-server file redirection bug in sftp downloads and scp remote-to-remote copies, argument truncation past the 9th argument in internal-sftp, and a client-side use-after-free during host key re-exchange. It also adds experimental post-quantum signatures combining ML-DSA 44 and Ed25519, and makes ssh/sshd disconnect peers sending non-KEX messages during post-authentication key re-exchange. _Track OpenSSH security fixes like these on daily.dev before rolling out a server upgrade._ ### Why does sshd now terminate the connection if SECCOMP or NO_NEW_PRIVS fails to enable on Linux? Starting with OpenSSH 10.4, failures to enable the seccomp sandbox or NO_NEW_PRIVS on Linux are treated as fatal errors instead of being logged and ignored. Previously sshd continued running to support systems lacking these features; administrators on such systems must now explicitly disable the sandbox at configure time rather than relying on the old silent fallback. _Developers hardening sshd deployments can follow OpenSSH sandboxing changes on daily.dev._ ### When did OpenSSH switch scp to use the SFTP protocol by default instead of the legacy scp/rcp protocol? OpenSSH 9.0, released April 8, 2022, made scp use the SFTP protocol by default instead of legacy scp/rcp. This removes the need for double-quoting shell metacharacters in remote filenames, though it changes how paths relative to another user's home directory (like ~user/file) are expanded, and the old behavior can be restored with the -O flag. _Anyone migrating scp workflows can check protocol-breaking changes like this on daily.dev before upgrading._ ## Community take How the wider developer community reacted, aggregated from 2 discussions and 36 comments across hackernews (as of 2026-09-14). **TL;DR:** The community is broadly positive about OpenSSH's new releases and security posture, with most discussion centering on the project's nuanced stance on AI-assisted bug reports rather than the technical changes themselves. There's genuine debate about what exactly the project permits regarding AI contributions. **Sentiment:** 55% positive · 30% mixed · 15% skeptical **The case for** - The new `ssh -Z` flag that lists public keys in the order they'll be tried is praised as a long-overdue quality-of-life improvement. - Welcoming AI-assisted security reports while requiring human triage and analysis is seen as a pragmatic response to the threat landscape. - More frequent releases to get bugfixes out faster is viewed positively given that adversaries may independently discover the same bugs. **The pushback** - Some commenters feel the project's AI policy is ambiguous or inconsistently applied, especially given OpenBSD's copyright concerns about AI-generated code. - The release notes webpage itself was called out as difficult to read. - SSH still lacks a host-header mechanism for reverse-proxying multiple services on a single IP. **By community** - hackernews (positive): Discussion is largely constructive, focused on parsing the AI bug-report policy and appreciating practical new features like `ssh -Z`, with only minor frustrations about missing features and page readability. **Hottest debate:** Whether OpenSSH/OpenBSD actually welcomes AI assistance broadly or only AI-assisted security bug reports, and what copyright implications AI-generated code carries for the project. **Open questions** - Could SSH adopt something analogous to TLS ESNI to enable encrypted server-name indication and allow reverse-proxying on a single IP? - Will OpenSSH formally clarify its policy on AI-generated code contributions versus AI-assisted security reports? - How will more frequent releases affect downstream packagers and distributions? **Highlights** > "[..] a security bug identified by AI tools is subsequently independently discovered by a different researcher. This suggests that adversaries who do not report bugs to OSS projects are likely to be able to discover these bugs too. Given this, the OpenSSH team will, for now, be making more frequent releases to get bugfixes into users' hands more quickly rather than batching them until the next planned release." > — [alpn on hackernews](https://news.ycombinator.com/item?id=49262579) > > ssh(1): add a "ssh -Z user@host" mode that prints the keys that will be tried for public key authentication in the order that they will be used. Oh, that's a nice new feature:) > — [yjftsjthsd-h on hackernews · 2 comments](https://news.ycombinator.com/item?id=49262651) > This was in the context of a contribution to add (IIRC) ext4 filesystem support to OpenBSD. In this case, I was worried that the AI was just regurgitating code that was in its training corpus because how many ext4 implementations are there? I think AI generated bugfixes and smaller features that don't duplicate fairly unique pieces of work in other projects are much less problematic from a copyright perspective at least. > — [djmdjm on hackernews](https://news.ycombinator.com/item?id=49267789) > Darn, still no host headers so we can reverse proxy on a single ip > — [qudat on hackernews · 2 comments](https://news.ycombinator.com/item?id=49264752) **Source threads** - [hackernews](https://news.ycombinator.com/item?id=49261895) · 99 points · 36 comments - [hackernews](https://news.ycombinator.com/item?id=49254118) · 3 points · 0 comments ## Similar posts on daily.dev - [OpenSSH 10.4 released](https://daily.dev/posts/openssh-10-4-released-hvdxib33z) · LWN.net · 0 upvotes · 0 comments - [OpenSSH 10.3 released](https://daily.dev/posts/openssh-10-3-released-krgsb6m3v) · LWN.net · 0 upvotes · 0 comments --- Tags: [#security](https://daily.dev/tags/security), [#quantum-computing](https://daily.dev/tags/quantum-computing), [#cryptography](https://daily.dev/tags/cryptography), [#ssh](https://daily.dev/tags/ssh) [View this post on daily.dev](https://daily.dev/posts/openssh-release-notes-iatm6rseu) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"OpenSSH: Release Notes","url":"https://daily.dev/posts/openssh-release-notes-iatm6rseu","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/openssh-release-notes-iatm6rseu"},"datePublished":"2026-07-07T16:17:31.186Z","dateModified":"2026-10-15T02:22:47.256Z","description":"OpenSSH release notes covering versions 9.9 through 10.4. 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