Fedify 2.1.24

Released on September 21, 2026.

@fedify/fedify

• Fixed the inbox accepting activities from any actor at all. Fedify verified the signature on an incoming delivery, but took the signing key's own word for whom it belonged to: the owner of a CryptographicKey and the controller of a Multikey were believed as served, even though the key document and the claim inside it come from the same host. Anyone with an ordinary HTTP server could therefore have an activity accepted as coming from any actor in the world, whether or not that actor existed. All three inbound authentication paths were affected—HTTP Signatures, Linked Data Signatures, and Object Integrity Proofs—and the latter two require no HTTP signature on the request at all. A key's claimed owner is now resolved and has to link back to the key before the key is usable, and a key that names no owner of its own is attributed to the actor whose document carried it. [GHSA-q9f8-5hc7-898f]
• Fixed getKeyOwner(), and therefore Context.getSignedKeyOwner(), accepting a key document dressed up as another origin's actor document. A host that served a key could describe itself as any actor and list the key as that actor's own, which let an attacker pass an authorized fetch under a borrowed identity and read whatever access control had reserved for it. Only the origin that serves an actor id can now speak for it. [GHSA-q9f8-5hc7-898f]
• Public keys cached before this release are no longer read back, since the owner recorded in them was never verified. Applications using the built-in key cache need no action; those passing a custom KeyCache implementation to verifyRequest(), verifyJsonLd(), or verifyObject() should discard its contents once on upgrade. [GHSA-q9f8-5hc7-898f]
• Fixed an SSRF vulnerability in outbound activity delivery that allowed inbox URLs and redirects to target private network addresses. Delivery now checks each destination unless allowPrivateAddress is explicitly enabled for local testing. [GHSA-f59r-8gcj-68f2]
• Fixed unbounded reads of authenticated documents, NodeInfo responses, and inbox bodies that could exhaust memory. JSON bodies are now limited to 16 MiB. Oversized inbox requests receive 413 Content Too Large. [GHSA-mc44-6cfg-2v6w]

@fedify/redis

• Fixed RedisKvStore.set() failing when the ttl option was not a whole number of seconds. The duration was handed to Redis SETEX unchanged, and SETEX takes only whole seconds, so the write was rejected with ERR value is not an integer or out of range instead of being stored with a rounded expiry. The TTL is now rounded up to the next whole second. A zero or negative duration, which SETEX also rejects, now stores the value for one second, the shortest expiry that command can express. The one-second granularity is SETEX's rather than Redis's; SET with PX supports millisecond expiries. [#1028, #1034 by Heewon Chae]

@fedify/vocab-runtime

• Fixed unbounded reads of remote JSON-LD and HTML documents that could exhaust memory. JSON responses are now limited to 16 MiB after decompression; HTML discovery is limited to 1 MiB. [GHSA-mc44-6cfg-2v6w]

@fedify/webfinger

• Fixed unbounded reads of WebFinger descriptors that could exhaust memory. Responses are now limited to 16 MiB after decompression; oversized responses return null. [GHSA-mc44-6cfg-2v6w]