CVE-2026-55455 json
Appsmith: SSRF in REST API / GraphQL datasource plugins via insufficient host denylist
published 2026-06-24 4 mo ago modified 2026-10-25 14 d ago also BIT-appsmith-2026-55455 , EUVD-2026-39111 , GHSA-m23h-pvf3-2m7p
- cvss
- 9.1
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.4%
- EPSS 0.4% chance of exploitation in 30 days, percentile 33%
- public exploits
- 0
- none known
Summary
Appsmith is a platform to build admin panels, internal tools, and dashboards. Prior to 2.1, the outbound HTTP host filter applied by WebClientUtils (used by the REST API and GraphQL datasource plugins) validates hosts against an exact-match string denylist. The comprehensive address-class check (loopback, any-local, link-local, fc00::/7) exists only on a separate code path used by SMTP, not by the HTTP plugin path. As a result, an authenticated user can craft outbound requests that reach loopback-bound services inside the container. This vulnerability is fixed in 2.1.
Patch / fix
- bitnami appsmith 2.1.0
- appsmith appsmith 2.1
CISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- no
- Technical impact
- partial
- Assessed
- 4 mo ago
Exploit prediction
0.39% chance of exploitation in the next 30 days, higher than 33% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- github.com https://github.com/appsmithorg/appsmith/security/advisories/GHSA-m23h-pvf3-2m7p referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 5.3 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N |
| CNA | 4.0 | 5.3 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:N/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 |
| NVD | 3.1 | 9.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N |
| OSV | 3.1 | 9.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| bitnami | appsmith | <2.1.0 |
2.1.0 |
Affected products
- appsmithorg appsmith
Classification
- Weakness
-
- CWE-918 Server-Side Request Forgery
References
-
github.com
/appsmithorg/appsmith/security/advisories/GHSA-m23h-pvf3-2m7p
exploit, third-party-advisory, advisory
-
nvd.nist.gov
/vuln/detail/CVE-2026-55455
web
Sources
- CVE List CVE-2026-55455
- NVD CVE-2026-55455
- OSV BIT-appsmith-2026-55455
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