Vulnerabilities in pkg:golang/github.com/crowdsecurity/crowdsec
PACKAGECVE-2026-44981 is a MODERATE denial of service vulnerability (CWE-409: Improper Handling of Highly Compressed Data (Data Amplification)) affecting CrowdSec LAPI libraries in the Go ecosystem. The issue involves denial of service via unbounded gzip decompression. Remediation is available by upgrading affected packages to version 1.7.8.
pkg:golang/github.com/crowdsecurity/crowdsec
Vulnerability advisories affecting package pkg:golang/github.com/crowdsecurity/crowdsec. Select an advisory below to view technical details or fixes.
| Advisory ID | CVE / NVD | Severity | Summary |
|---|---|---|---|
| GHSA-273h-gvwr-c3qj | CVE-2026-44981 | MODERATE | CrowdSec LAPI: Denial of Service via Unbounded Gzip Decompression |
| GHSA-rw47-hm26-6wr7 | CVE-2026-44982 | HIGH | CrowdSec AppSec silently drops request body for chunked / HTTP-2 requests |
CVE-2026-44981 at a Glance
How to Fix CVE-2026-44981
To remediate this vulnerability, upgrade all affected CrowdSec LAPI dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.
Upgrade github.com/crowdsecurity/crowdsec to 1.7.8
Run the following command in your project directory to verify that all resolved dependencies use the patched release:
inspect dependencies for github.com/crowdsecurity/crowdsec
How to Check if You Are Affected
To determine whether your application is affected by CVE-2026-44981, inspect your project dependencies for CrowdSec LAPI:
inspect dependencies for github.com/crowdsecurity/crowdsec
Analyze the terminal output to locate any version of CrowdSec LAPI in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 1.7.8), your application is affected.
Note: Verify declared build manifests and deployed runtime container environments.
Technical Details
Vulnerability Mechanism & Technical Analysis
This vulnerability is classified under CWE-409: Improper Handling of Highly Compressed Data (Data Amplification), where the product does not handle or incorrectly handles a compressed input with a very high compression ratio that produces a large output. In CrowdSec LAPI, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.
Source Advisory Statement
CVE-2026-44981 Affected CrowdSec LAPI Versions
1 component(s)| Product / Package | Ecosystem | Affected Versions | Fixed Version |
|---|---|---|---|
|
github.com/crowdsecurity/crowdsec
|
Go |
≥ 1.7.0
< 1.7.8
|
1.7.8
|
References
Frequently Asked Questions
What is CVE-2026-44981?
Which CrowdSec LAPI versions are affected?
What version fixes CVE-2026-44981?
Is github.com/crowdsecurity/crowdsec affected?
What CWE is associated with CVE-2026-44981?
How can I check Go dependencies for CVE-2026-44981?
Machine-readable OSV JSON
OSV v1.5 Schema
{
"schema_version" : "1.4.0",
"id" : "GHSA-273h-gvwr-c3qj",
"modified" : "2026-06-12T20:24:21Z",
"published" : "2026-05-27T19:57:28Z",
"aliases" : [ "CVE-2026-44981" ],
"summary" : "CrowdSec LAPI: Denial of Service via Unbounded Gzip Decompression",
"details" : "The LAPI router uses `gin-contrib/gzip` with `DefaultDecompressHandle` globally (`pkg/apiserver/controllers/controller.go`).\nThis middleware decompresses incoming request bodies without enforcing a maximum decompressed size. \n\nThe endpoints `/v1/watchers` or `/v1/watchers/login` require no authentication.\nAn attacker can send small gzip-compressed JSON payloads that, when decompressed, result in hundreds of MB of valid JSON occupying server memory.\nSending enough requests concurrently will cause LAPI to allocate excessive heap memory, leading the OS to forcibly terminate the process.\n \nThis vulnerability is not exploitable from the network in default configurations, as LAPI only listens on the loopback interface.\nIf developers' applications are using a multi-server setup, LAPI will be exposed in the network, in which case they are at risk if untrusted IPs can access it.\n \n### Impact\n\nExploiting this vulnerability will make LAPI unreachable, meaning that bouncers will not be able to fetch new decisions (but existing decisions will still be enforced) and log processors will not be able to send alerts, effectively denying the creation of new decisions.\n\n### Workarounds\n\nIf the LAPI is exposed on the network (either directly or through a reverse proxy), for example in the case of a multi-server deployment, restrict access to trusted IP addresses.",
"severity" : [ {
"type" : "CVSS_V4",
"score" : "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U"
} ],
"affected" : [ {
"package" : {
"ecosystem" : "Go",
"name" : "github.com/crowdsecurity/crowdsec"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "1.7.0"
}, {
"fixed" : "1.7.8"
} ]
} ]
} ],
"references" : [ {
"type" : "WEB",
"url" : "https://github.com/crowdsecurity/crowdsec/security/advisories/GHSA-273h-gvwr-c3qj"
}, {
"type" : "PACKAGE",
"url" : "https://github.com/crowdsecurity/crowdsec"
}, {
"type" : "WEB",
"url" : "https://github.com/crowdsecurity/crowdsec/releases/tag/v1.7.8"
} ],
"database_specific" : {
"cwe_ids" : [ "CWE-409" ],
"severity" : "MODERATE",
"github_reviewed" : true,
"github_reviewed_at" : "2026-05-27T19:57:28Z",
"nvd_published_at" : null
}
}