CrowdSec LAPI: Denial of Service via Unbounded Gzip Decompression
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- Present
- Impact type
- —
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Fixed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA and GitHub.
Summary
CrowdSec offers crowdsourced protection against malicious IPs. From 1.7.0 until 1.7.8, the LAPI router used gin-contrib/gzip with DefaultDecompressHandle globally in pkg/apiserver/controllers/controller.go, causing /v1/watchers and /v1/watchers/login to decompress unauthenticated gzip-compressed JSON request bodies without enforcing a maximum decompressed size and allowing excessive heap allocation that can make LAPI unreachable. This issue is fixed in version 1.7.8.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| crowdsecurity | crowdsec | 1.7.0 to before 1.7.8 | 1.7.8 | Patch available | CNA |
| — | github.com/crowdsecurity/crowdsec (Go) | 1.7.0 to before 1.7.8 | 1.7.8 | Patch available | GHSA-273h-gvwr-c3qj |
- crowdsec Vendorcrowdsecurity Affected 1.7.0 to before 1.7.8 Fixed in 1.7.8 Patch available CNA
- github.com/crowdsecurity/crowdsec (Go) Vendor— Affected 1.7.0 to before 1.7.8 Fixed in 1.7.8 Patch available GHSA-273h-gvwr-c3qj
Remediation
- Fix · CNA crowdsec (crowdsecurity) Fixed in 1.7.8
- Fix · GHSA-273h-gvwr-c3qj github.com/crowdsecurity/crowdsec (Go) Fixed in 1.7.8 Advisory →
Timeline
- 2026-10-02 Threatist record created from CVE-2026-44981
- 2026-10-03 Alias added: GHSA-273h-gvwr-c3qj
References
Other 5
- https://github.com/crowdsecurity/crowdsec/security/advisories/GHSA-273h-gvwr-c3qj
- https://github.com/crowdsecurity/crowdsec/commit/54a0dfe6c16b7687b0da6634e0b19ef0f5d9bb30
- https://github.com/crowdsecurity/crowdsec/commit/56d0d6915f7f25941dc5b4f484028646f6601a37
- https://github.com/crowdsecurity/crowdsec
- https://github.com/crowdsecurity/crowdsec/releases/tag/v1.7.8
More crowdsecurity vulnerabilities
- TI-2026-32842 CrowdSec AppSec silently drops request body for chunked / HTTP-2 requests CVSS 3.1HIGH 7.2
Sources
- CVE-2026-44981 · CVE Program
- CVE-2026-44981 · NVD
- FIRST EPSS
- GHSA-273h-gvwr-c3qj · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences