Answer in brief
CVE-2021-22569 records a High severity (CVSS 7.5) vulnerability in A potential Denial of Service issue in protobuf-java. The current sources do not mark it as known exploited. The current feed maps com.google.protobuf:protobuf-java (maven), com.google.protobuf:protobuf-java (maven), com.google.protobuf:protobuf-java (maven), com.google.protobuf:protobuf-kotlin (maven) and additional mapped packages. Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 7.5. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps com.google.protobuf:protobuf-java (maven), com.google.protobuf:protobuf-java (maven), com.google.protobuf:protobuf-java (maven), com.google.protobuf:protobuf-kotlin (maven) and additional mapped packages. Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| com.google.protobuf:protobuf-javamaven | >=0 <3.16.1 | 3.16.1 |
| com.google.protobuf:protobuf-javamaven | >=3.18.0 <3.18.2 | 3.18.2 |
| com.google.protobuf:protobuf-javamaven | >=3.19.0 <3.19.2 | 3.19.2 |
| com.google.protobuf:protobuf-kotlinmaven | >=3.18.0 <3.18.2 | 3.18.2 |
| com.google.protobuf:protobuf-kotlinmaven | >=3.19.0 <3.19.2 | 3.19.2 |
| google-protobufrubygems | >=0 <3.19.2 | 3.19.2 |
Published upstream
Jan 7, 2022
Evidence: source:osv:source_dates:source-dates:recordSource modified
Sep 10, 2026
Evidence: source:osv:source_dates:source-dates:recordFirst seen by HOL
Aug 7, 2026
## Summary A potential Denial of Service issue in protobuf-java was discovered in the parsing procedure for binary data. Reporter: [OSS-Fuzz](https://github.com/google/oss-fuzz) Affected versions: All versions of Java Protobufs (including Kotlin and JRuby) prior to the versions listed below. Protobuf "javalite" users (typically Android) are not affected. ## Severity [CVE-2021-22569](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-22569) **High** - CVSS Score: 7.5, An implementation weakness in how unknown fields are parsed in Java. A small (~800 KB) malicious payload can occupy the parser for several minutes by creating large numbers of short-lived objects that cause frequent, repeated GC pauses. ## Proof of Concept For reproduction details, please refer to the oss-fuzz issue that identifies the specific inputs that exercise this parsing weakness. ## Remediation and Mitigation Please update to the latest available versions of the following packages: - protobuf-java (3.16.1, 3.18.2, 3.19.2) - protobuf-kotlin (3.18.2, 3.19.2) - google-protobuf [JRuby gem only] (3.19.2)
Quoted source text, attributed separately from HOL analysis.