CVE-2026-86231
A security flaw has been discovered in mwiede jsch up to 2.28.5. Affected is the function getRevokedKeys of the file src/main/java/com/jcraft/jsch/KnownHosts.java. Performing a manipulation of the argument known_hosts results in improper check for certificate revocation. The attack is possible to be carried out remotely. The attack is considered to have high complexity. The exploitability is told to be difficult. The exploit has been released to the public and may be used for attacks. Upgrading to version 2.28.6 is able to address this issue. The patch is named 194a2f76a5c0f1c3f778565be3fd66bcafc42d23. You should upgrade the affected component.
What this means for your business
- An attacker can use it remotely, over a network, without a login, and without anyone at your company clicking anything.
- FIRST's prediction model gives it a 0.3% chance of attack attempts being seen in the next 30 days, ranking above 19% of all known flaws.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
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Scoring
- CVSS
- 3.7 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N- CVSS v4
- 2.9
- Weakness
- CWE-298
- Assigned by
- cna@vuldb.com
Dates
- Published
- 2026-09-06
- Last modified
- 2026-09-11
- Sources
- NVD
References
- https://github.com/mwiede/jsch/
- https://github.com/mwiede/jsch/commit/194a2f76a5c0f1c3f778565be3fd66bcafc42d23
- https://github.com/mwiede/jsch/issues/1091
- https://github.com/mwiede/jsch/pull/1098
- https://github.com/mwiede/jsch/releases/tag/jsch-2.28.6
- https://vuldb.com/cve/CVE-2026-86231
- https://vuldb.com/submit/898485
- https://vuldb.com/vuln/399388
- https://vuldb.com/vuln/399388/cti