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Comments (155)

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  solatic
  Necessary qualifier: for browser-based user sessions.Plenty of good uses for JWTs for service-to-service communication.edit: I read some of the linked stuff, e.g. https://paragonie.com/blog/2017/03/jwt-json-web-tokens-is-ba... . Please, if JWTs are such a horrifically insecure standard, go ahead and publish your means for hacking AWS STS's AssumeRoleWithWebIdentity , or don't publish and just exploit it by launching cryptominers in every Fortune 500 production AWS account. Let me know when you inevitably succeed, because JWTs are so insecure, right? /sarcasm
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  tracker1
  JWTs are insecure... even when using trusted, rsa/ppk based signing methods? not shared secrets.JWTs are too long lived... Nothing is stopping you from limiting the JWT lifetime and having a refresh model against an authentication authority... I mean, even if you use cookie based sessions, you're storing somewhere... you can have a jwt valid for 5-15min. 15minutes is roughly the cache timing for many authorization systems including Entra... and even a 5min token with a refresh system can be used fine from a browser.Lastly, I prefer to have identity/auth separated from the application/api services... it externalizes context and JWT per request is easier to deal with than some shared cache/state system that may intermittently fail as opposed to a signed token that you can verify the signature against known authorities.
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  littlecranky67
  In sessions vs. JWT revocation lists, there is an argument in favor of JWT revocation lists. JWTs have a limited expiry timestamp, so you only ever need to maintain a revocation list for tokens not expired yet. Given that you probably only have a fraction of JWTs revoked compare to valid JWTs in circulation, you only need to query a very small dataset for each request.When using sessions, your list of valid sessions is probably orders of magnitudes higher that the revocation list - thus the data lookup costs and the storage cost of that statefulness is higher.Plus, the article mentions JWTs are stateless but that is usually not true. You mostly not only validate the JWT, but also obtain a matching identity object (i.e. user details) for each request to see if the user is still enabled/authorized to do whatever he does. You can leverage stuff such as per-user revocation lists, or a minimum_issued_at that will validate any JWT iat field. This allows the "Logout from all devices" pattern, where that action will simply set a user's minimum_issued_at field to $NOW. All previous tokens will thus be revoked, without individuall revocation list checks.
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  ApolloFortyNine
  This links to some other blog post for the bulk of it's 'why', and that blog post mostly seems to be annoyed about "You cannot invalidate individual JWT tokens". Which every time I've implemented, the general guideline is to check for invalidated nonces somewhere. Which resolves that random blog posts second point too.>The JWT specification itself is not trusted by security experts.This feels like it needs more evidence than just one blog post. And that blog post seems to just largely blame bad implementations? Something that will plague any standard.Overall, I don't know what I expected clicking a random gist link.
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  rdegges
  =0 I stumbled across this post and was thinking that it's interesting to see this topic trending now, since I've done a lot of work on it in the past. Then I clicked through and realized the author is linking to some of my stuff! What a blast from the past.Anyhow, there are way smarter people than myself who have covered this topic extensively over the years, but I still think that, even in 2026, JWTs are the wrong tools for web auth. They're fine to use for service-to-service stuff, but if you have the option, just use PASETO -- it solves a lot of the issues!
• mekoka
  Every once in a while an article with a sensational title against JWTs pops up in here and I have to wonder if something new was discovered. But nope. It always boils down to the same "can't invalidate it" complaint, which can be addressed with a viable blacklist structure (simple in-memory key/values, runtime bloom filter or trie, or other fast indexes). Then there are the vague "it's insecure" claims which when looked at closely, come down to "some people use it wrong".
• Grollicus
  I'm right now adding rabbitmq for notification pushing to a website. Using JWT authentication to control where and what clients are allowed to read, with short lifetimes and regular token refresh.I don't see another setup that comes close to the ease of setting this up - add an endpoint that provides jwt tokens to valid sessions, done. With user-individual permissions.
• andy_ppp
  Okay, so hack into a site that uses JWTs for login, if it’s so insecure we should be seeing loads of attacks against them right? Stolen tokens everywhere being used to impersonate people and other things. For example I believe ChatGPT is using Auth0 which uses JWTs, so you can hack this insecure token system? Should be easy right given the extremity of the warning that JWT is the big problem here.
• blixt
  JWTs are fine, seems a bit sensationalist title...Some nice topics to talk about instead:- When to use an encrypted value (and symmetric or asymmetric), vs. a random (but secret) value, vs. a signed value (readable but not tamperable)- Where to put these values (memory, localStorage, cookies)- How to make sure these values don't last forever, and whether you need to be able to revoke them (make them invalid before their natural expiration timestamp)
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  himata4113
  Hmh, the way I usually use JWTs is as an authentication cache. You obtain your authentication token from the auth service which grants you permission to other services.This has several advantages, the main one being that sub-services do not have to interact with the authentication database or have access to the capability to mint tokens (this assumes you use RS256 not HMAC). So if a sub-service gets compromised it's not as devastating as a service which has access to the authentication database.If you have sensitive data inside the token you should use JWEs, although they're not as good because you have to ask an internal service (which has the private key) to decode the token each time you want to use it.My typical layout is {"id": (uuid), "scopes": ["scope:read/write"]}.Also they're really neat for SPA's as you can have your static site server validate that the JWE with the public key before serving any resources. The way I use this is that I have my static site compiled to /(scope)/path and the static service will not serve pages that you cannot access anyway. This is very useful in cases where you have administrative panels where you don't want to expose to users what capabilities your backend has or/and expose the internal service paths that can be attacked.My lifetime for JWT's is around 5 minutes for "backend access", things like /me are cached in localStorage unless explicitely instructed in /refresh to drop localStorage cache. My request handler in my SPA applications detects "refresh required" and refreshes the token.I think most of the blame here belongs to node/next and python libraries. I write my backends in strongly typed languages and my frontend is always made out of precompiled static pages. My current setup for the frontend is using VITE with prerendered pages for landing and normal SPA for applications.With all of that said I strongly disagree with this entire gist. JWT is as secure as you want it to be.
• eranation
  Been in this rabbit hole since JWT shipped. As others have mentioned, cookies have their own risks, you're now juggling both XSS and CSRF, and the CSRF defenses (SameSite, tokens) do nothing against XSS since that's a same-origin attacker.Just to clarify, httpOnly/sameSite isn't useless under XSS the way localStorage is. XSS can't read a httpOnly cookie, so it can't exfiltrate the credential, it can only perform the attack during the session from the victim's browser. A JWT in localStorage can be reused offline for its entire lifetime. Also worth separating: localStorage is the exposure, not JWT. Just please for the love of all that's good and pretty, don't store a JWT in a httpOnly cookie.
• harrall
  JWT is secure.I just noticed that after JWT was created, people would just slap on JWT like an end-all because JWT sounded secure and they thought it was all that they needed to do.That’s my only “problem” with JWT but to be honest, people will build insecure systems anyway.
• asattarmd
  JWTs are secure in the sense that they are tamper-proof. And that's all you need for a session token (plus the revocation list). There's nothing inherently insecure about JWTs.
• bastawhiz
  One of the linked posts explaining why you shouldn't use JWTs is bizarre at best:https://paragonie.com/blog/2017/03/jwt-json-web-tokens-is-ba...It boils down to "there were bugs in some of the libraries" and then goes on to recommend you...pull in libsodium and do it yourself??? This is ludicrous advice that I simply can't take seriously. All software has bugs. The whole Internet lost its shit with Heartbleed, but we still use TLS and OpenSSL.> The JWT specification is specifically designed only for very short-live tokens (~5 minute or less).I've never heard this before and can't find any evidence to back this claim up. RFC 7519 doesn't make any such claim.
• genghisjahn
  I've used JWTs for a number of server to server interactions and they are amazing for what they are. I've also told many a front end team member to NOT use them.
• anon
  undefined
• green_wheel
  > The JWT specification is specifically designed only for very short-live tokens (~5 minute or less). Sessions need to have longer lifespans than that.Citation needed. Where does it say this?
• adamddev1
  I remember learning to make sites back around 2019 and seeing so many blog posts and hype around JWTs. It seemed like "this was the way to do it!" But I couldn't understand why session cookies weren't the better, simpler solution. I just used session cookies. Nice to be vindicated in retrospect.
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  BlackFly
  If I understand the point being made here then the idea is that a stateless session via a cryptographically verified bearer token needs a stateful revocation list to eliminate hijacking (a user logout should completely invalidate the login but a bearer token would otherwise continue to be valid) and if you are maintaining state then you can just use a complete stateful session and avoid the complexity of the cryptography.This point is not made very clearly and is buried by overemphasising JWTs instead of just quickly pointing them out as an example of a stateless session. But yeah, it is a good point.
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  miiiiiike
  Security doesn't start or end with JWTs.A user wants to access a read-only resource with an invalid JWT? Envoy bounces it without passing the request through to the backend. Valid JWT? Let the request through without having to look up any session information. No DB, no cache, no session server hit. Fast.A user wants to change a password, email address, or add an authenticator? First, require a password, second, require a second factor. If all of that checks out, look for the JWT access token in a revocation list that is only accessed during sensitive, infrequent, requests like these. If the token has been revoked, 403.Tokens are dropped from the revocation list once the original access token's TTL has passed. Which should be low. I use 5 minutes. Most sessions on my site last 4-10 minutes.Worst case scenario, a malicious user is able to access certain read-only resources for a few minutes.
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  gabrielsroka
  2019
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  vova_hn2
  One of the articles that TFA links to [0] contains the following paragraphs:> And there are more security problems. Unlike sessions - which can be invalidated by the server whenever it feels like it - individual stateless JWT tokens cannot be invalidated. By design, they will be valid until they expire, no matter what happens. This means that you cannot, for example, invalidate the session of an attacker after detecting a compromise. You also cannot invalidate old sessions when a user changes their password.> You are essentially powerless, and cannot 'kill' a session without building complex (and stateful!) infrastructure to explicitly detect and reject them, defeating the entire point of using stateless JWT tokens to begin with.I'm not sure that this is entirely true. Typically, the total number of non-expired issued tokens is much higher than the number of invalidated unexpired tokens. Therefore, if you store only invalidated tokens and delete them when they get expired, you can significantly reduce the amount of required storage and the cost of lookup.Although, in any real application the performance gains will be minuscule (compared to the cost of, you know, everything else. Auth is just a small part) and probably not worth the extra complexity.[0] "Stop using JWT for sessions" - http://cryto.net/~joepie91/blog/2016/06/13/stop-using-jwt-fo...
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  feelingsonice
  PASETO is great but there's not enough ecosystem support
• lucassz
  > You can't securely have truly stateless authentication without having massive resources, see the cryto.net link above.I don't think the cryto.net post really explains why this is true (at least in a way that would be made different by "massive resources").
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  cjoelrun
  I ain't never gonna stop!
• Aeolun
  At this point this just feels like an old man shouting at the clouds.
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  hparadiz
  JWTs are for authenticating an already trusted system with another system.Using them as the primary source of truth is an anti-pattern like the blog post is actually saying.
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  szmarczak
  No need to stop. The XSS argument also applies when using cookies.JWTs are just tokens like session data but in JSON format. What format you choose to go with doesn't matter.You can keep storing JWTs in local storage and still be secure. Discord removes it on page load and restores it when the tab is closed.Also if your website is susceptible to XSS, skill issue, exactly like in the case of SQL injections. That wouldn't have happened had people used the right tools and not played with fire.
• stickfigure
  Like most "always do this" or "never do this" articles, this one is dumb.If you are operating at a scale where you can simply store session data in the database and look it up every time, that's a fine way to operate. At some scale this approach becomes a problem, and it's faster/cheaper/simpler to store some limited data on the client (signed).Yes there are complexities to both approaches. That's fine.
• jongjong
  JWTs are extremely useful for storing basic non-secret authentication info. Session IDs are not as good for most situations and force unnecessary database or memory store lookups. JWT is a more versatile authentication construct because it doesn't prevent you from doing that extra lookup but it also doesn't force you to.It's far better than a session ID in the sense that you can store an accountId inside a JWT and be confident about the identity of this user... The fact that you can get such confidence without any external lookups; just by looking at the token, is incredibly useful on its own. You can already seperate out unauthenticated guest users from authenticated users and you can tie their identities to real accounts without even checking the DB or session store. Banning is a separate concern. Being able to quickly, efficiently and reliably identify a user from the server-side is a necessity.The only real downside of JWTs which people point to is that they cannot be easily be revoked... But if you really need the ability to revoke quickly, you can easily have 10 minute expiries on your tokens and request refresh every 3 minutes or so... So if you want to ban someone, there would be a 10 minute delay which is acceptable for the vast majority of scenarios... You should handle rate limiting as a separate concern anyway if spam is the issue.For certain systems, a user may be making hundreds or thousands of requests in 10 minutes so you're saving a HUGE number of session ID lookups and it means that you don't need to run and maintain a separate Redis service or whatever else. Not to mention the additional latency which is added when you need to check Reddit before each operation.These blanket statements against JWT are not new. People have been misusing them and blaming the tech because they don't want to acknowledge that they made implementation mistakes.Any technology can be misused. It's foolish to misuse a perfectly good piece of tech and then use that as the basis to promote some alternative which has been through less battle-testing and which probably has even more gotchas which are yet to be discovered.As a senior engineer with 15+ years of experience, I've seen this cycle over and over again. The new tech is always presented as fool proof and it never never never is.
• ForHackernews
  I'm not convinced. All the PASETO objections[0] are things that have long since been addressed by every major JOSE implementation.[0] https://paragonie.com/blog/2017/03/jwt-json-web-tokens-is-ba...
• cyberax
  Stop using JWTs and instead use my copy of JWTs with all the same fundamental issues! But now it also has a custom snowflake serialization format!Yeah, right.JWTs are fine, as long as you use sane algorithms. The missing revocation really can be done by replicating revocation policies. E.g. a direct list of revoked tokens or a blanket "don't trust tokens before this timestamp".
• misano
  imo instead of random cookie u can carry some data in it and avoid more joins in database why not ?
• mgaunard
  A whole lot of nonsense from a web guy.Please, keep using JWTs, they do their job well: giving you an access or ID token that you can pass between applications and trust based on cryptographic signatures from an identity provider.
• scudsworth
  no
• waterTanuki
  Everyone has a strong opinion on how to implement auth yet seemingly no one has hard data or peer-reviewed research to back up said opinions.
• kobalsky
  I agree that using cookies is better for web sessions but I absolutely despise those using the boogeyman to shoo people away from stuff they don't like, instead of asking them to use their brains.> they are not secure.They are secure if they fit your risk profile, a blanket statement like this is just disinformation.Don't treat your peers like idiots.
• EGreg
  Over the past 15 years of developing secure web apps for various organizations, I ended up architecting solutions which had to deal correctly with ITP, webauthn, CHIPS, iframes and more.This year, I ended up publishing an open protocol that can be used for everything from secure authentication to API requests to micropayments, and it works with the existing Web stack and P256 curve with JSON serialization curves as well as EVM blockchains via K256 curve and EIP712 serialization.I encourage everyone to take a look at it and consider using it, so we can stop reinventing the wheel. Everything has already been deployed, it’s an extremely simple protocol, much simpler than JWT and requires no global registry.https://openclaiming.orghttps://github.com/OpenClaimingIt is also used in stuff like https://safebots.github.io/Safecloud/
• hoppp
  What if I put a jwt in a session cookie?The post is not descriptive enoughIt should explain how to not store JWT instead of just saying JWT is bad.
• _el1s7
  I hate these type of clickbait articles
• anon
  undefined
• jheriko
  [dead]
• well_ackshually
  [dead]
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  dzonga
  due to the recent FIFA hack - just a reminder - stop using JWTs
• bijowo1676
  JWTs are in every bit superior to cookies