CVE-2026-89086
jose OCaml Improper RSA Signature Validation
Description
In the jose package before 0.11.0 for OCaml, library calls to validate an RSA signature only confirm that PKCS #1 decoding succeeds, and proceed to declare the signature valid without the required steps that involve the public key.
INFO
Published Date :
Sept. 10, 2026, 8:17 p.m.
Last Modified :
Sept. 10, 2026, 8:17 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-89086
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 | 8254265b-2729-46b6-b9e3-3dfca2d5bfca | ||||
| CVSS 3.1 | CRITICAL | [email protected] |
Solution
- Update the jose package to a secure version.
- Verify RSA signature validation logic.
- Ensure public key is used in validation.
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-2026-89086.
| URL | Resource |
|---|---|
| https://github.com/ulrikstrid/ocaml-jose/commit/cf17d991ec6a0d1997956b6c7799890f9c28879e | |
| https://osv.dev/vulnerability/OSEC-2026-19 |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-89086 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-2026-89086
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-2026-89086 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-89086 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]
Sep. 10, 2026
Action Type Old Value New Value Added Description In the jose package before 0.11.0 for OCaml, library calls to validate an RSA signature only confirm that PKCS #1 decoding succeeds, and proceed to declare the signature valid without the required steps that involve the public key. Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N Added CWE CWE-347 Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/89xxx/CVE-2026-89086.json">CVE-2026-89086</a> Added Reference https://github.com/ulrikstrid/ocaml-jose/commit/cf17d991ec6a0d1997956b6c7799890f9c28879e Added Reference https://osv.dev/vulnerability/OSEC-2026-19