CVE-2026-57566
Readest: Unauthenticated SSRF / open request proxy in /api/opds/proxy
Description
Readest is a modern, feature-rich ebook reader designed for seamless cross-platform access and an intuitive reading experience. Prior to 0.11.10, the unauthenticated /api/opds/proxy route in apps/readest-app/src/app/api/opds/proxy/route.ts accepted an attacker-controlled URL and fetched it server-side without restricting the scheme, blocking private, loopback, link-local, or metadata hosts, or revalidating destinations during automatic redirect following. The route also accepted caller-controlled outbound headers and Authorization values and reflected the upstream status and response body. A remote attacker could use the service as an open request proxy and, on Node, Docker, or other self-hosted deployments with internal-network access, retrieve cloud metadata or internal-service responses. Cloudflare Workers deployments restrict access to link-local and private destinations, which reduces the internal-network impact there, but the unauthenticated public fetch-and-reflect behavior remains. This issue is fixed in version 0.11.10.
INFO
Published Date :
Nov. 4, 2026, 10:18 p.m.
Last Modified :
Nov. 4, 2026, 10:18 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-57566
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | CRITICAL | [email protected] |
Solution
- Update Readest application to version 0.11.10.
- Verify proxy route restrictions on your deployment.
- Implement strict URL validation for fetched resources.
- Restrict access to internal and sensitive hosts.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-57566.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-57566 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-57566
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-57566 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-57566 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by [email protected]
Nov. 04, 2026
Action Type Old Value New Value Added Description Readest is a modern, feature-rich ebook reader designed for seamless cross-platform access and an intuitive reading experience. Prior to 0.11.10, the unauthenticated /api/opds/proxy route in apps/readest-app/src/app/api/opds/proxy/route.ts accepted an attacker-controlled URL and fetched it server-side without restricting the scheme, blocking private, loopback, link-local, or metadata hosts, or revalidating destinations during automatic redirect following. The route also accepted caller-controlled outbound headers and Authorization values and reflected the upstream status and response body. A remote attacker could use the service as an open request proxy and, on Node, Docker, or other self-hosted deployments with internal-network access, retrieve cloud metadata or internal-service responses. Cloudflare Workers deployments restrict access to link-local and private destinations, which reduces the internal-network impact there, but the unauthenticated public fetch-and-reflect behavior remains. This issue is fixed in version 0.11.10. Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:L/A:N Added CWE CWE-918 Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/57xxx/CVE-2026-57566.json">CVE-2026-57566</a> Added Reference https://github.com/readest/readest/commit/495783d04516d05b2eb10f8f8bad297d436b36de Added Reference https://github.com/readest/readest/pull/4638 Added Reference https://github.com/readest/readest/releases/tag/v0.11.10 Added Reference https://github.com/readest/readest/security/advisories/GHSA-c7mm-g2j2-98cx