CVE-2026-15541will-moss Isaiah Master Websocket server.go Server.Handle authorization
- 6.9MediumCVSS base score
- 0.54%Exploitation in 30 daysEPSS · top 54% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- YesPublic exploitsa reference or SSVC says so
Description
A flaw has been found in will-moss Isaiah up to 1.36.9. The impacted element is the function Server.Handle of the file app/server/server/server.go of the component Master Websocket Handler. Executing a manipulation of the argument Agent can lead to missing authorization. It is possible to launch the attack remotely. The pull request to fix this issue awaits acceptance.
Public exploit
An exploit or proof of concept is public: anyone can try it against an unpatched system. CISA's SSVC rates its exploitation: a proof of concept is public.
Timeline
ID reserved
By VulDB
- 1 day later
· 1 day later
Published
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| VulDBCNA (assigner) | 4.0 | Medium6.9 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:X |
| VulDBCNA (assigner) | 3.1 | High7.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L/E:X/RL:X/RC:R |
| VulDBCNA (assigner) | 3.0 | High7.3 | CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L/E:X/RL:X/RC:R |
| VulDBCNA (assigner) | 2.0 | High7.5 | AV:N/AC:L/Au:N/C:P/I:P/A:P/E:ND/RL:ND/RC:UR |
| NVDNVD · Deferred | 4.0 | Medium6.9 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/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 |
- EPSS (exploitation in 30 days)
- 0.54% · top 54% of all CVEs (13 Nov 2026)
- CISA SSVC
- Exploitation: poc · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 6.9.
Affected products
References
References7
- VDB-377891 | will-moss Isaiah Master Websocket server.go Server.Handle authorization (opens in a new tab)vdb-entrytechnical-description
- VDB-377891 | CTI Indicators (IOB, IOC, IOA) (opens in a new tab)signaturepermissions-required
- CVE-2026-15541 | CVE Analysis and Report (opens in a new tab)third-party-advisory
- Submit #855074 | will-moss Isaiah 1.36.9 CWE-862 Missing Authorization (opens in a new tab)third-party-advisory
- https://github.com/will-moss/isaiah/issues/34 (opens in a new tab)issue-tracking
- https://github.com/will-moss/isaiah/pull/35 (opens in a new tab)issue-trackingpatch
- https://github.com/will-moss/isaiah/ (opens in a new tab)product
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-43298 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-15541)Record last updated .