CVE-2026-103956 json
Missing authentication for critical function in Loom for AWS
published last mo. modified last mo. also EUVD-2026-91770
- cvss
- 10.0
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 2.5%
- EPSS 2.5% chance of exploitation in 30 days, percentile 84%
- public exploits
- 0
- none known, plus a Nuclei check
Summary
Missing authentication for critical function in the authentication dependency in Loom for AWS before 1.6.1 allowed remote actors to obtain super-admin authority over the agent control plane, including registering tool servers, reading stored integration credentials, and rewriting the IAM role policies attached to managed agent roles, via any request to the application API in a deployment where no identity provider is configured.
To remediate this issue, users should upgrade to version 1.6.1 or later.
Patch / fix
Is CVE-2026-103956 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- total
- Assessed
- last mo.
Exploit prediction
2.49% chance of exploitation in the next 30 days, higher than 84% of all scored CVEs (FIRST EPSS, 2026-11-09).
Exploits and checks
- Nuclei template Loom for AWS < 1.6.1 - Unauthenticated Super-Admin Access nuclei detection template
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 10.0 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H |
| CNA | 4.0 | 10.0 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H |
| CNA | 4.0 | 10.0 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/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 |
Affected products
- AWS loom
Classification
References
-
github.com
/awslabs/loom/releases/tag/v1.6.1
release-notes, patch
-
aws.amazon.com
/security/security-bulletins/2026-124-aws/
vendor-advisory
-
github.com
/awslabs/loom/security/advisories/GHSA-vgmj-998f-r8mp
third-party-advisory
Sources
- CVE List CVE-2026-103956
- NVD CVE-2026-103956
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.