MEDIUMCVSS v4 5.7Vulnerability

CVE-2026-111762

### *Impact.** Push notification bearer tokens and authentication credentials submitted by clients are written to server log files in cleartext. Any operator, log aggregation system, or attacker with log access can read these secrets and use them to authenticate to the client's push notification endpoints, potentially sending forged task status updates. **Where.** `transport/rest/src/main/java/org/a2aproject/sdk/transport/rest/handler/RestHandler.java:676` in `parseRequestBody` **What.** The `parseRequestBody` method logs the entire JSON request body at `SEVERE` level when `JsonFormat.parser().merge()` throws `InvalidProtocolBufferException`. This method is called from `createTaskPushNotificationConfiguration` (line 377), where the body contains client-supplied push notification bearer tokens (field `token`) and authentication credentials (field `authentication.credentials`). These secrets are written to server log files in full. **Exploit scenario.** A client creates a push notification configuration by POSTing to `/v1/tenants/{tenant}/tasks/{taskId}/pushNotificationConfigs` with a body containing `{"url": "https://client.example.com/webhook", "token": "secret-bearer-token", "authentication": {"scheme": "Bearer", "credentials": "oauth-access-token"}, "extraField": "value"}`. The extra field causes `JsonFormat.parser().merge()` to throw `InvalidProtocolBufferException`. The entire body including `secret-bearer-token` and `oauth-access-token` is logged at SEVERE level. An attacker with log access retrieves the cleartext credentials. **Preconditions.** - Attacker must have access to server log files (centralized logging, log aggregation, shared infrastructure, or insider access) - Push notification capability must be enabled - A request body must fail protobuf deserialization while being valid JSON (unknown fields with strict parsing, schema mismatches) **Fix.** Do not log the raw request body. Log only a sanitized summary — body length and content type, not cont

Properties

Severity
medium
Summary
A2A Java SDK: Push notification credentials logged in cleartext on protobuf parse failure
Nvd fetched at
2026-10-20T21:14:08.448323+00:00
Cvss severity
MEDIUM
Cvss score
5.7
Retrieved at
2026-10-21T01:23:59+00:00
Ghsa published
2026-10-20T21:08:33Z
Source url
https://github.com/advisories/GHSA-x32g-jvvm-4725
Ghsa updated
2026-10-20T21:08:34Z
Ghsa id
GHSA-x32g-jvvm-4725
Last source
GitHub Advisory Database
Score
5.7
Cvss version
4.0
Cve id
CVE-2026-111762
Cvss vector
CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:H/VI:N/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
First seen by Signal
2026-10-20T17:10:14+00:00
Is ghsa only
false
Vector
CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:H/VI:N/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
Published at
2026-10-20T15:17:13.210
Last modified
2026-10-20T19:55:49.343

Related Entities (3)

Explore deeper with Ninja Signal's threat intelligence graph

CVE-2026-111762 (CVSS v4 5.7) — Ninja Signal Threat Intelligence | Ninja Signal