ag-ui-protocol ag-ui Transport Decoder input validation
Affects @ag-ui/client up to 0.0.58 when the server responds with the protobuf media type, which skips schema validation. No fixed version is listed.
Written by anthropic/claude-haiku-5.5 from the sources below. Verify against them.
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- Published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- A 0-100 score for how much a CVE matters across the industry: exploitation, exposure, how widely the software is used, severity and whether a fix exists.What do these mean? →
- 13/100 · provisional
- How many real-world setups can hit the bug, from the vendor's advisory and CISA data. It does not know your setup.What do these mean? →
- Specific setups only
- Fix
- Fix or patch referenced
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
The ag-ui-protocol ag-ui software, up to and including version 0.0.58, is affected through its Transport Decoder component, where input is not properly validated. Successful exploitation could allow a remote attacker to manipulate the decoder's handling of data, and the vendor has released a patch.
Read the original description
A vulnerability was detected in ag-ui-protocol ag-ui up to 0.0.58. Affected by this vulnerability is an unknown functionality of the component Transport Decoder Handler. The manipulation results in improper input validation. The attack may be launched remotely. The exploit is now public and may be used. The patch is identified as 660182b973a44b8eda5484b14b88eb9cc251edc4. It is suggested to upgrade the affected component.
What to do
Check whether your setup matches what the bug needs.
Affected package is @ag-ui/client up to version 0.0.58. The response must use the protobuf media type, so the client selects the protobuf decoder instead of the SSE path. On the protobuf path, decoded events are emitted without schema validation.Apply the patch listed under Evidence.
Timeline
- CVE published
- First seen by cve.now
Affected versions
- ag-ui-protocol ag-ui
0.0.1, 0.0.2, 0.0.3, 0.0.4, 0.0.5, 0.0.6, 0.0.7, 0.0.8, 0.0.9, 0.0.10, 0.0.11, 0.0.12, 0.0.13, 0.0.14, 0.0.15, 0.0.16, 0.0.17, 0.0.18, 0.0.19, 0.0.20, 0.0.21, 0.0.22, 0.0.23, 0.0.24, 0.0.25, 0.0.26, 0.0.27, 0.0.28, 0.0.29, 0.0.30, and 28 more
Evidence 9
- Advisory
- Advisory
- Advisory
- Advisory
- Patch
- Patch
- Patch
- Exploit
- Repository
Corrections
None so far.
Something wrong on this page? Report an error. Every fix is listed here.
Questions about CVE-2026-120236
What does this mean?
Events decoded over the protobuf path are passed straight into the client state machine without schema validation. Malformed events, such as type-confused or extra-field events, can then cause downstream logic errors. The source describes this as a validation bypass beyond availability.Source: github.com
Am I affected, and how do I check?
The affected package is @ag-ui/client up to and including 0.0.58, verified against the published npm release. The issue applies when the response uses the protobuf media type, because the client then uses the protobuf decoder instead of the SSE path. To check, look at the @ag-ui/client version in your project's package.json or lockfile.Source: github.com
What should I do about it?
The checked facts do not list a fixed version, so no upgrade target can be named. Check the project's advisory or the npm package for a release that adds schema validation to the protobuf path.Source: github.com
Is it being exploited?
It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked.Source: cve.now feed data