CVE-2026-62979
jack: upstream error responses expose backend and peer credentials
Description
jack lets users share media libraries through their Radarr/Sonarr stack, peer-to-peer. Prior to 0.1.0, `middleware/handle-error.ts` serializes raw `FetchError` objects into HTTP responses. `lib/servers/base.ts` attaches outbound request headers on upstream non-success responses and schema-validation failures; the public `extras` field in `lib/errors/FetchError.ts` remains enumerable and is emitted by JSON serialization. These headers include the internal Radarr/Sonarr `X-Api-Key` and custom connector headers such as `CF-Access-Client-Secret`. `lib/redact.ts` redacts logs and spans but not this response path. Any client with the shared peer API key, plus Cloudflare Access credentials if required by the deployment, can force an error without a race or user interaction. `GET /peer/items/:id` and `GET /servers/health` can expose the internal media-server key, while `GET /torznab/download/:id` can expose another peer's key and Cloudflare Access secrets. The /peer/search and /items routes catch these errors and are not affected. Disclosed internal keys grant full administrative control of the corresponding Radarr/Sonarr instance, crossing the intended boundary between friends' shared peer access and private backend credentials. This issue is fixed in version 0.1.0.
INFO
Published Date :
Oct. 30, 2026, 9:17 p.m.
Last Modified :
Oct. 30, 2026, 11:17 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-62979
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 | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 4.0 | HIGH | [email protected] |
Solution
- Update jack to version 0.1.0.
- Review and secure API keys.
- Limit peer access to trusted individuals.
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-2026-62979.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-62979 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-2026-62979
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-2026-62979 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-62979 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.
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CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Oct. 30, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-62979', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-10-30T21:18:23.166510Z'} -
New CVE Received by [email protected]
Oct. 30, 2026
Action Type Old Value New Value Added Description jack lets users share media libraries through their Radarr/Sonarr stack, peer-to-peer. Prior to 0.1.0, `middleware/handle-error.ts` serializes raw `FetchError` objects into HTTP responses. `lib/servers/base.ts` attaches outbound request headers on upstream non-success responses and schema-validation failures; the public `extras` field in `lib/errors/FetchError.ts` remains enumerable and is emitted by JSON serialization. These headers include the internal Radarr/Sonarr `X-Api-Key` and custom connector headers such as `CF-Access-Client-Secret`. `lib/redact.ts` redacts logs and spans but not this response path. Any client with the shared peer API key, plus Cloudflare Access credentials if required by the deployment, can force an error without a race or user interaction. `GET /peer/items/:id` and `GET /servers/health` can expose the internal media-server key, while `GET /torznab/download/:id` can expose another peer's key and Cloudflare Access secrets. The /peer/search and /items routes catch these errors and are not affected. Disclosed internal keys grant full administrative control of the corresponding Radarr/Sonarr instance, crossing the intended boundary between friends' shared peer access and private backend credentials. This issue is fixed in version 0.1.0. Added CVSS V4.0 AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:H/SI:H/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CWE CWE-200 Added CWE CWE-209 Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/62xxx/CVE-2026-62979.json">CVE-2026-62979</a> Added Reference https://github.com/roziscoding/jack/commit/2b296b5137acca476f34a23b692dd8c04ae1f148 Added Reference https://github.com/roziscoding/jack/releases/tag/v0.1.0 Added Reference https://github.com/roziscoding/jack/security/advisories/GHSA-8gw5-7585-4997