vulnerability / NVI-00017615 / Revision 1
MessagePack-CSharp: JSON conversion APIs can recurse without consistent depth enforcement
GitHub lists this reviewed advisory for MessagePack, MessagePack. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.
This report has not inspected your inventory, configuration, deployed build, reachability or evidence. A catalog listing and a severity score do not establish exposure or compromise.
01 / Meaning
Why it matters
Published affected context helps an owner decide what evidence to gather. This report has not examined your application.
02 / Applicability
The affected context
Affected versions, configuration prerequisites and known exclusions are public. Confirm each one against the deployed service.
MessagePack
source listed< 2.5.301
## Summary MessagePack-CSharp's JSON conversion helpers contain multiple recursion paths that do not consistently enforce a depth limit. These paths are in the JSON conversion component rather than normal typed MessagePack deserialization. Three related issues are covered by this advisory: 1. `MessagePackSerializer.ConvertFromJson` recursively processes nested JSON arrays and objects in `FromJsonCore()` without consulting `MessagePackSecurity.MaximumObjectGraphDepth`. 2. `TinyJsonReader.ReadNextToken()` recursively consumes comma and colon separator characters, allowing even malformed JSON with long separator runs to consume one stack frame per character. 3. `MessagePackSerializer.ConvertToJson` applies depth checks to arrays and maps, but the typeless extension branch for ext-100 recursively calls `ToJsonCore()` without applying `MessagePackSecurity.DepthStep(ref reader)`. Each path can allow attacker-controlled input to exhaust the process stack and trigger an uncatchable `StackOverflowException` instead of failing with a catchable parse or serialization exception. ## Impact Applications are affected when they call MessagePack-CSharp JSON conversion APIs on attacker-control
MessagePack
source listed>= 3.0, < 3.1.7
## Summary MessagePack-CSharp's JSON conversion helpers contain multiple recursion paths that do not consistently enforce a depth limit. These paths are in the JSON conversion component rather than normal typed MessagePack deserialization. Three related issues are covered by this advisory: 1. `MessagePackSerializer.ConvertFromJson` recursively processes nested JSON arrays and objects in `FromJsonCore()` without consulting `MessagePackSecurity.MaximumObjectGraphDepth`. 2. `TinyJsonReader.ReadNextToken()` recursively consumes comma and colon separator characters, allowing even malformed JSON with long separator runs to consume one stack frame per character. 3. `MessagePackSerializer.ConvertToJson` applies depth checks to arrays and maps, but the typeless extension branch for ext-100 recursively calls `ToJsonCore()` without applying `MessagePackSecurity.DepthStep(ref reader)`. Each path can allow attacker-controlled input to exhaust the process stack and trigger an uncatchable `StackOverflowException` instead of failing with a catchable parse or serialization exception. ## Impact Applications are affected when they call MessagePack-CSharp JSON conversion APIs on attacker-control
03 / Response
What to do next
- investigate
Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.
Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system. GitHub Advisory Database
A fixed release is not deployment evidence.
Check current vendor support and compatibility. After making a change, verify the deployed build and relevant runtime conditions. Keep the evidence, owner and time. An updated lockfile alone does not prove what is running.
04 / Limits
What this report cannot establish
- Customer inventory, deployment, reachability and exploitation have not been inspected.
05 / Provenance
Sources you can inspect
Each assertion retains its source. Mirrored records may repeat one underlying publisher; additional links are not independent corroboration.
- GHSA-cj9g-3mj2-g8vv ↗
GitHub Advisory Database · vendor advisory
Observed . GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.
Public revision history
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- Revision 1 ·
First indexed by Null; source disclosure date is shown separately.