canto-saas-api: OAuth credentials exposed in URL query string and exception messages (CVE-2026-55375) | HOL Guard CVE

Medium severityCVE-2026-55375GHSA-37PM-83G7-R22V

canto-saas-api: OAuth credentials exposed in URL query string and exception messages

Answer in brief

CVE-2026-55375 records a Medium severity vulnerability in canto-saas-api: OAuth credentials exposed in URL query string and exception messages. The current sources do not mark it as known exploited. The current feed maps jleehr/canto-saas-api (composer), jleehr/canto-saas-api (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Sep 15, 2026Updated Sep 15, 2026Source checked Sep 17, 2026First seen by HOL Jun 19, 2026Material review Sep 15, 2026

Upstream Advisory

Key facts

Risk: Medium
Exploitation: Not marked as known exploited
Affected software: 2 mapped packages or products
Fix availability: Available

Why this deserves its current priority

A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps jleehr/canto-saas-api (composer), jleehr/canto-saas-api (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
jleehr/canto-saas-apicomposer	<=2.0.0	3.0.0
jleehr/canto-saas-apigeneric	< 3.0.0	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for jleehr/canto-saas-api, jleehr/canto-saas-api.
Review the reported fix. Update jleehr/canto-saas-api to 3.0.0 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Sep 15, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 15, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Jun 19, 2026

Sources and claim methodology

Upstream source description

canto-saas-api is a PHP library for interacting with the Canto SaaS API. Prior to version 3.0.0, OAuth2Request::getQueryParams() places app_id, app_secret, refresh_token, and code in the URL query string of token POST requests, allowing access logs, proxy logs, and APM traces to persist the credentials in plaintext. When a token request fails, OAuth2::obtainAccessToken() also passes the credential-bearing Guzzle request URI into AuthorizationFailedException, so application logs and error trackers can record the same secrets. An attacker with access to affected telemetry can obtain Canto credentials and use them to request access tokens for the tenant. This issue is fixed in version 3.0.0.

Quoted source text, attributed separately from HOL analysis.