Vulnerability from bitnami_vulndb
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.
{
"affected": [
{
"package": {
"ecosystem": "Bitnami",
"name": "appsmith",
"purl": "pkg:bitnami/appsmith"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "2.1.0"
}
],
"type": "SEMVER"
}
],
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N",
"type": "CVSS_V3"
}
]
}
],
"aliases": [
"CVE-2026-55455"
],
"database_specific": {
"cpes": [
"cpe:2.3:a:appsmith:appsmith:*:*:*:*:*:*:*:*"
],
"severity": "Critical"
},
"details": "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.",
"id": "BIT-appsmith-2026-55455",
"modified": "2026-09-10T15:46:03.895Z",
"published": "2026-06-29T05:37:58.273Z",
"references": [
{
"type": "ADVISORY",
"url": "https://github.com/appsmithorg/appsmith/security/advisories/GHSA-m23h-pvf3-2m7p"
},
{
"type": "WEB",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-55455"
}
],
"schema_version": "1.6.2",
"summary": "Appsmith: SSRF in REST API / GraphQL datasource plugins via insufficient host denylist"
}
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.