# CVE-2026-77620: Vector logstash source denial of service via nested compression

Source: https://junglewise.ai/threats/cve-2026-77620-vector-is-a-high-performance-observability-data-pipeline-from-0  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-22. Updated: 2026-09-26  
License: CC BY 4.0 with a link back

CVE-2026-77620 · Severity: info · Published 2026-09-22

Vector is a data pipeline tool used to collect and process logs across infrastructure. An attacker without authentication can send specially crafted compressed log frames to the default listener, causing the application to recursively decompress them and exhaust the worker process. This crashes Vector and halts log collection for all tenants sharing the same pipeline.

Technologies: [Datadog Vector](https://junglewise.ai/threats/technologies/vector). Vendors: [Datadog](https://junglewise.ai/threats/vendors/datadog).

## Quick answers

**Is CVE-2026-77620 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-77620 being exploited in the wild.

**How severe is CVE-2026-77620?** Informational severity, published 22 September 2026.

**Which products and versions are affected?** Datadog Vector 0.15.0 to 0.57.0.

**Is there a fix for CVE-2026-77620?** A patch was published on 2026-07-13: Fixed in v0.57.0 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-77620 attacked?** It is attacked over the network, in a hosted service.

**Am I affected by CVE-2026-77620?** Check whether you run Datadog Vector at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

The logstash source in Vector versions 0.15.0–0.57.0 does not validate nesting depth of compressed frames, allowing recursive decompression attacks. An unauthenticated remote attacker reaching the default 0.0.0.0:5044 listener can send nested compressed payloads that amplify decompressed size, causing stack exhaustion and worker thread abort. The fix (v0.57.0) rejects compressed frames nested inside compressed frames.

## Affected products

- Datadog Vector 0.15.0 to 0.57.0

## Timeline

- 2026-09-22: disclosed
- 2026-07-13: patched: Fixed in v0.57.0

## References

- [https://github.com/vectordotdev/vector/commit/57fed991083c9a43d5fda2d5b3bf4718aedf6526](https://github.com/vectordotdev/vector/commit/57fed991083c9a43d5fda2d5b3bf4718aedf6526)
- [https://github.com/vectordotdev/vector/pull/25825](https://github.com/vectordotdev/vector/pull/25825)

## Related threats

- [Datadog Vector Denial of Service via memory exhaustion in HTTP and gRPC ingest](https://junglewise.ai/threats/cve-2026-39197-datadog-vector-denial-of-service-via-memory-exhaustion-in-http)
- [Datadog Vector SQL injection in ClickHouse sink KeyPartitioner](https://junglewise.ai/threats/cve-2026-39196-datadog-vector-sql-injection-in-clickhouse-sink-keypartitioner)