# CVE-2026-102877: Fider before 0.38.0 SSRF via DNS rebinding in webhook validation

> Attackers can exploit DNS rebinding in webhook validation to force the Fider server to access internal services or cloud metadata endpoints.

- **Severity:** Low 2.1 (`CVSS:4.0/AV:N/AC:H/AT:P/PR:H/UI:N/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 29 Sep 2026
- **Updated:** 30 Sep 2026
- **Also known as:** GHSA-j753-jwgq-fwxj, GHSA-whx4-hxwq-qgjh

## What is CVE-2026-102877?

CVE-2026-102877 is a low-severity server-side request forgery vulnerability in getfider fider, published on 29 Sep 2026. An attacker needs administrator access to exploit it, with no action from the victim.

### Official description

Fider before 0.38.0 contains a server-side request forgery vulnerability due to a time-of-check time-of-use gap in URL validation for webhooks and custom OAuth provider endpoints. Administrators controlling DNS can perform DNS rebinding attacks to make the Fider server send requests to internal services or cloud metadata endpoints.

Weakness: CWE-918 (Server-Side Request Forgery)

## Which versions are affected by CVE-2026-102877?


## How do I fix CVE-2026-102877?

No fix has been published for CVE-2026-102877 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-102877 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-102877 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-102877 and fix it if it is affected.

What it is: CVE-2026-102877 is a low-severity server-side request forgery vulnerability in getfider fider, published on 29 Sep 2026. An attacker needs administrator access to exploit it, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-102877 exists.

Affected product: getfider fider. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-102877/ (Markdown: https://insights.sbomify.com/CVE-2026-102877/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-102877
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-102877
- OSV: https://osv.dev/vulnerability/CVE-2026-102877

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-102877/
Summaries are generated and may contain mistakes; the official description above is the record.