CVE-2026-55375 is a medium-severity security vulnerability in jleehr/canto-saas-api (composer), affecting versions <= 2.0.0. It is fixed in 3.0.0.
Summary In affected versions, the OAuth2 token request sends appid, appsecret, refreshtoken and code as URL query parameters of the POST request to https://oauth.<domain>/oauth/api/oauth2/token. Request URLs are commonly recorded in access logs, proxy logs and APM traces, so the application secret and refresh token can be persisted in plain text outside the application's control. In addition, when the token request fails, the Guzzle exception message, which contains the full request URI including the credentials, was passed unmodified into the AuthorizationFailedException thrown by OAuth2::obtainAccessToken(). Applications that log exceptions or forward them to error trackers (e.g. Sentry) may therefore have recorded the app secret in their logs. ## Impact An attacker with access to web server logs, proxy logs, APM tracing data or application error logs of a consumer of this library can obtain the Canto appsecret, refreshtoken or authorization code and use them to obtain access tokens for the Canto tenant. ## Patches Fixed in 3.0.0: OAuth credentials are sent in the form-encoded POST body instead of the URL query string (RFC 6749 §2.3.1). OAuth2Request::getQueryParams() now returns null; the parameters are available via getFormParams(). Exception messages are sanitized before being rethrown: the values of appsecret, refresh_token and code are masked (including url-encoded, differently cased and JSON-embedded variants). ## Workarounds If you cannot upgrade: Treat web server, proxy and APM logs of systems performing Canto OAuth requests as secret material and restrict access to them. Catch AuthorizationFailedException in your application and strip the query string from the message before logging or forwarding it. If your logs may have been exposed, rotate the affected Canto app secret.
CVE-2026-55375 has a CVSS score of 5.3 (Medium). The vector is network-reachable, low privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment.
A fixed version is available (3.0.0). Upgrading removes the vulnerable code path.
composer
jleehr/canto-saas-api (<= 2.0.0)jleehr/canto-saas-api → 3.0.0 (composer)Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter instead of chasing every advisory.
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Upgrade jleehr/canto-saas-api to 3.0.0 or later to resolve this vulnerability.
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CVE-2026-55375 is a medium-severity security vulnerability in jleehr/canto-saas-api (composer), affecting versions <= 2.0.0. It is fixed in 3.0.0.
CVE-2026-55375 has a CVSS score of 5.3 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
jleehr/canto-saas-api (composer) versions <= 2.0.0 is affected.
Yes. CVE-2026-55375 is fixed in 3.0.0. Upgrade to this version or later.
Whether CVE-2026-55375 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
Upgrade jleehr/canto-saas-api to 3.0.0 or later.