CVE-2026-55407

Buffa is a pure-Rust Protocol Buffers implementation with first-class protobuf editions support. Prior to 0.8.0, the decode_unknown_field function in buffa's protobuf decoder allocated heap memory in proportion to untrusted input (unknown fields in the serialized protobuf) without enforcing an allocation budget, affecting any message decoded from untrusted input using code generated with preserve_unknown_fields=true (the default); a small, well-formed payload of nested unknown fields inside a StartGroup could trigger roughly 22x memory amplification (for example a 64 MiB input forcing about 1.4 GB of heap allocation), and length-delimited unknown fields could be sized arbitrarily, so an unauthenticated attacker could crash a process through memory exhaustion because the top-level message size cap did not account for in-decode amplification. This issue is fixed in version 0.8.0.

CVSS

No CVSS.

References

Link	Resource
https://github.com/anthropics/buffa/commit/278fa43fcff661d4ee6bd83b75955a153d4281fc
https://github.com/anthropics/buffa/pull/184
https://github.com/anthropics/buffa/releases/tag/v0.8.0
https://github.com/anthropics/buffa/security/advisories/GHSA-f9qc-qg88-7pq5

Configurations

No configuration.

History

16 Jul 2026, 17:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-16 17:16

Updated : 2026-07-16 19:16

NVD link : CVE-2026-55407

Mitre link : CVE-2026-55407

CVE.ORG link : CVE-2026-55407

JSON object : View

Products Affected

No product.

CWE

CWE-400

Uncontrolled Resource Consumption

CWE-770

Allocation of Resources Without Limits or Throttling

CWE-789

Memory Allocation with Excessive Size Value

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