Question About Content Authenticity Assumptions in Podcasting 2.0

[Kfir-G]

Hi,

I’m trying to better understand the trust assumptions behind Podcasting 2.0 and the podcast namespace.

Specifically, I’m curious whether there are any mechanisms - current or planned - that address content integrity or provenance at the feed or episode level, or whether the ecosystem intentionally relies on the same implicit trust model as traditional RSS.

This is not about identifying issues or proposing changes, but simply about understanding the design boundaries and what is considered in-scope versus out-of-scope for the protocol.

Thanks in advance - I’m looking for clarity on the design assumptions rather than implementation details

[picard102]

Implicit trust.

[jamescridland]

I suspect you'd need to highlight what, particularly, you want "trust" for.

Right now, I'm unaware of any specific trust added by additional Podcasting 2.0 features. ("Podcasting 2.0" is just a set of additional RSS tags, built to go in a standard RSS 2.0 feed, so by design, there's not anything that would break things.) Fundamentally, once you've found an RSS feed, then elements of content integrity ("Is this really the audio without any edits") or provenance ("is this really Diary of a CEO, or is this a copy with crappy ads dropped in") are irrelevant. The source of truth is the RSS feed, after all.

The way Google Podcasts attempted to fix this was to require the link from the RSS feed to a website to be linked back, using a LINK REL. So, if the podcast feed you just found was purporting to be Diary of a CEO, then it would link to the Diary of a CEO website, and that would have a LINK REL back to the podcast feed.

This failed. Partially it failed because it's not trivial to add a LINK REL to some websites, especially if they're just a Substack or a Facebook page. Partially, it failed because there's no trust that the Diary of a CEO website is actually the Diary of a CEO website, so all that's really being trusted here is a link to somewhere else on the internet, rather than any actual guarantee that it's from someone particularly. And, partially it failed because a surprising number of podcasts don't have websites of their own.

I'm liking the idea of fixing that somehow - especially in a world where there are plenty of copies of the big podcasts, with programmatic ads added on. Ideas would be welcome.

[Kfir-G]

Thanks for the thoughtful replies - they helped clarify the design boundaries quite a bit.

Following this discussion, I wrote a short article that tries to frame podcasting through a supply-chain lens, focusing on trust assumptions rather than vulnerabilities or proposals:

Podcasts as a Supply Chain: A Missing Security Model : https://kfir-g.dev/blog/blogs/2025-12-30_podcasts-as-a-supply-chain-missing-security-model/

For context: I come from a security engineering background and have worked on supply-chain related systems. I’m also a heavy podcast listener, which is what motivated me to look at podcast RSS this way.

The article isn’t a critique of Podcasting 2.0 or RSS, and it doesn’t suggest changes. It’s mainly an attempt to document the implicit trust model and make the assumptions explicit, especially given scale, duplication, ads, and monetization.

Sharing in case it’s useful for context happy to hear thoughts.

[jamescridland]

I read it yesterday! Interesting piece.

The title implies critique - "a missing security model".

These missing guarantees:

• Cryptographic authentication of episodes
• Integrity guarantees for audio files
• Immutability after publication

... not quite as easy to fix as you'd think. The audio file that you hear isn't the audio file that I hear. I'm in Australia, you're probably not, so therefore I will get ads for Hungry Jacks and Commonwealth Bank, while you'll get ads for your own local brands. The audio files we hear are made upon download: so the RSS feed can't offer any integrity guarantees, nor immutability guarantees.

6. What Major Hosting Platforms Validate - and What They Don’t
   Platforms like Spotify for Creators, Podbean, RSS.com, and others validate operational aspects:

Typically validated: XML correctness, required RSS fields, MIME types, file accessibility
Typically not validated: Cryptographic integrity, content provenance, immutability, intent verification
This aligns with treating podcasting as a CMS problem, not a supply-chain problem.

I think this para is confused about a podcast hosting platform (which makes an RSS file and hosts the audio), and a podcast playback platform (like Apple Podcasts, Pocket Casts, or Antennapod). It's typically the playback platform that would validate RSS feeds and ingest them (Antennapod will do that on-device, Apple and Pocket Casts do that in their own server farm). Podcast Index validates and ingests as well, for its API.

"If it comes from the feed it must be legitimate" is, you think, not reasonable for today's mainstream podcasting. I'd disagree - coming from the feed still works as a security model. The real issue is - "is this the real feed". What's happened in the past is bad actors copying audio files and adding adverts - this story highlights that. A search in a podcast app might return the "real" feed and the "fake" feed. That's definitely something that needs fixing - but I'm rather unclear how to do that.

Interesting article. Food for thought!

[theDanielJLewis]

Toss into this that proxy-based podcast apps, such as Spotify and now Apple Podcasts (since iOS 14.5), do not connect audiences directly with the RSS feed and instead stand between the audience in the feed. Thus, this gives those top platforms the ability to insert, remove, or alter anything delivered to your audience. That's where such authenticity would possibly be most needed, but also where it would most likely be ignored by the offending parties.

[Kfir-G]

Thanks for the thoughtful response this really helps clarify things.

I agree that episode-level integrity or immutability is tricky today, given dynamic ad insertion, CDN variation, and region-specific audio. There often isn’t a single canonical audio artifact that can be signed or hashed meaningfully.

The core issue I’m highlighting is less about protecting the audio itself and more about ensuring a listener or app discovers the correct, authoritative feed in the first place. Once a feed is accepted as legitimate, the existing trust model generally works, as you note.

Where the model strains is in discovery and duplication: copied feeds, re-hosted content with added ads, and multiple indistinguishable feeds for the same show. In that sense, the missing piece seems closer to feed identity and provenance than traditional content integrity.

The intent of the article wasn’t to frame this as a vulnerability, nor to suggest that Podcasting 2.0 should solve it today, but to describe current trust boundaries and ask whether identity-level signals are explicitly in scope or intentionally left out.

Appreciate you taking the time to engage definitely food for thought.