# CVE-2026-34148: Fedify unbounded redirect following resource exhaustion in document loader

Source: https://junglewise.ai/threats/cve-2026-34148-fedify-unbounded-redirect-following-resource-exhaustion-in  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-04-06. Updated: 2026-06-09  
License: CC BY 4.0 with a link back

CVE-2026-34148 · Severity: high · CVSS 7.5 · Published 2026-04-06

Fedify, a library used for building decentralized social media applications, is vulnerable to a denial-of-service attack. An attacker can provide a malicious link that forces the server into an infinite loop of web requests. This can exhaust the server's resources, leading to slow performance or a complete service outage for all users.

Technologies: [Fedify](https://junglewise.ai/threats/technologies/fedify), [@fedify/fedify (npm)](https://junglewise.ai/threats/technologies/fedify-fedify). Vendors: [Fedify](https://junglewise.ai/threats/vendors/fedify), [npm](https://junglewise.ai/threats/vendors/npm).

## Quick answers

**Is CVE-2026-34148 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-34148 being exploited in the wild.

**How severe is CVE-2026-34148?** High severity, with a CVSS score of 7.5, published 6 April 2026.

**Which products and versions are affected?** Fedify < 1.9.6, >= 1.10.0, < 1.10.5, >= 2.0.0, < 2.0.8, = 2.1.0; Fedify Vocab Runtime < 2.0.8, = 2.1.0; @fedify/fedify (npm) SEMVER:introduced=0,fixed=1.9.6; @fedify/vocab-runtime (npm) SEMVER:introduced=0,fixed=2.0.8.

**Is there a fix for CVE-2026-34148?** Yes. @fedify/fedify (npm): upgrade to 1.9.6 or later; @fedify/vocab-runtime (npm): upgrade to 2.0.8 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-34148 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-34148?** Check whether you run Fedify, Fedify Vocab Runtime, @fedify/fedify (npm) or one of the others listed at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- @fedify/fedify (npm): upgrade to 1.9.6 or later

  ```sh
  npm install @fedify/fedify@1.9.6
  ```

- @fedify/vocab-runtime (npm): upgrade to 2.0.8 or later

  ```sh
  npm install @fedify/vocab-runtime@2.0.8
  ```


## Technical details

The vulnerability exists in the remote document loader and authenticated document loader of @fedify/fedify. These components recursively follow HTTP 3xx redirects without enforcing a maximum redirect count or implementing loop detection. An attacker can trigger this by providing a malicious ActivityPub keyId or actor URL that points to a self-referential redirect loop. Because failed lookups are only cached locally for the duration of a single request, the attack can be repeatedly executed to exhaust CPU, connection slots, and outbound bandwidth. Patches are available in versions 1.9.6, 1.10.5, 2.0.8, and 2.1.1.

## Affected products

- fedify-dev @fedify/fedify < 1.9.6, >= 1.10.0, < 1.10.5, >= 2.0.0, < 2.0.8, = 2.1.0
- fedify-dev @fedify/vocab-runtime < 2.0.8, = 2.1.0

## Identifiers

- CVE-2026-34148
- GHSA-gm9m-gwc4-hwgp

## Timeline

- 2026-04-04: disclosed: Initial publication by dahlia to fedify-dev/fedify
- 2026-04-06: advisory: NVD publication date
- 2026-04-07: advisory: GitHub Advisory Database publication date

## References

- [https://api.github.com/users/wrathsec](https://api.github.com/users/wrathsec)
- [https://github.com/wrathsec](https://github.com/wrathsec)
- [https://api.github.com/users/wrathsec/gists%7B/gist_id%7D](https://api.github.com/users/wrathsec/gists%7B/gist_id%7D)
- [https://api.github.com/users/wrathsec/repos](https://api.github.com/users/wrathsec/repos)
- [https://avatars.githubusercontent.com/u/237007125?v=4](https://avatars.githubusercontent.com/u/237007125?v=4)
- [https://api.github.com/users/wrathsec/events%7B/privacy%7D](https://api.github.com/users/wrathsec/events%7B/privacy%7D)

## Related threats

- [Fedify getNodeInfo() server-side request forgery](https://junglewise.ai/threats/cve-2026-62857-fedify-getnodeinfo-server-side-request-forgery)
- [Fedify SSRF via incomplete IPv4 validation in validatePublicUrl](https://junglewise.ai/threats/cve-2026-50131-fedify-ssrf-via-incomplete-ipv4-validation-in-validatepublicurl)
- [Fedify Linked Data Signature bypass via JSON-LD restructuring](https://junglewise.ai/threats/cve-2026-42462-fedify-linked-data-signature-bypass-via-json-ld-restructuring)
- [Fedify is a TypeScript library for building federated server apps powered by ActivityPub. Prior to versions 1.6.13, 1.7.14, 1.8.15, and 1.9.](https://junglewise.ai/threats/cve-2025-68475-fedify-redos-vulnerability-in-html-parsing-regex)
- [Fedify authentication bypass in ActivityPub inbox handler](https://junglewise.ai/threats/cve-2025-54888-fedify-authentication-bypass-in-activitypub-inbox-handler)