CVE-2026-53659

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Source
https://cve.org/CVERecord?id=CVE-2026-53659
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-53659.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-53659
Aliases
Published
2026-09-14T17:29:57Z
Modified
2026-09-16T03:46:27Z
Severity
  • 7.5 (High) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H CVSS Calculator
Summary
http4k: Unbounded gzip decompression in `ServerFilters.GZip` / `RequestFilters.GunZip` allowed memory-exhaustion DoS
Details

http4k is a functional toolkit for Kotlin HTTP applications. Prior to 4.51.0.0, 5.42.0.0, and 6.49.0.0, ServerFilters.GZip, RequestFilters.GunZip, and the underlying Gzip request-body decompression functions impose no limit on decompressed size. An unauthenticated client can send a small gzip-encoded request body that expands to gigabytes, exhausting the JVM heap and denying service to other clients. The fix uses SizeLimitedInputStream to enforce a default 10 MiB limit, causes ServerFilters.GZip and RequestFilters.GunZip to return 413 Request Entity Too Large, and causes other decompression paths to throw SizeLimitExceededException. This issue is fixed in versions 4.51.0.0, 5.42.0.0, and 6.49.0.0.

Database specific 
{
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
        "CWE-409"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53659.json",
    "unresolved_ranges": [
        {
            "extracted_events": [
                {
                    "fixed": "4.51.0.0"
                }
            ],
            "source": "AFFECTED_FIELD"
        }
    ]
}
References

Affected packages

Git / github.com/http4k/http4k

Affected ranges

Type
GIT
Repo
https://github.com/http4k/http4k
Events
Introduced
ed37b9043df6505b3369b8cb31bddbb0e7cd1b76
Introduced
c2a2f9f85e704385b864a34a91adaea2a3275a2e
Fixed
e41f40814305510d4f82e30bb0bcd12b9928292e
Fixed
911eb36ed34ce8a8ec494f64044b9d49756ec45a
Fixed
2618fe08f9801353012561ae1f1382fa2d37bac9
Fixed
9f9e02f8efbbe04e0c70f1c46eef5d9d9067ea5b
Database specific
Show details 
{
    "extracted_events": [
        {
            "introduced": "5.0.0.0"
        },
        {
            "fixed": "5.42.0.0"
        },
        {
            "introduced": "6.0.0.0"
        },
        {
            "fixed": "6.49.0.0"
        }
    ],
    "source": [
        "AFFECTED_FIELD",
        "REFERENCES"
    ]
}

Affected versions

0.*
0.0.0
5.*
5.0.0.0
5.1.0.0
5.1.1.0
5.1.1.1
5.1.2.0
5.1.2.1
5.10.0.0
5.10.1.0
5.10.2.0
5.10.3.0
5.10.4.0
5.10.5.0
5.10.6.0
5.10.7.0
5.11.0.0
5.11.1.0
5.12.0.0
5.12.1.0
5.12.2.0
5.12.2.1
5.13.0.0
5.13.0.1
5.13.1.0
5.13.2.0
5.13.4.0
5.13.4.1
5.13.5.0
5.13.6.0
5.13.6.1
5.13.7.0
5.13.8.0
5.13.9.0
5.14.0.0
5.14.1.0
5.14.2.0
5.14.4.0
5.14.5.0
5.15.0.0
5.16.0.0
5.16.1.0
5.16.2.0
5.17.0.0
5.18.1.0
5.18.2.0
5.19.0.0
5.2.0.0
5.2.1.0
5.20.0.0
5.21.0.0
5.21.1.0
5.21.2.0
5.22.0.0
5.23.0.0
5.24.0.0
5.24.1.0
5.25.0.0
5.25.1.0
5.26.0.0
5.26.1.0
5.27.0.0
5.28.0.0
5.28.1.0
5.29.0.0
5.3.0.0
5.30.0.0
5.30.1.0
5.31.0.0
5.31.1.0
5.32.0.0
5.32.1.0
5.32.2.0
5.32.3.0
5.32.4.0
5.33.0.0
5.33.0.1
5.33.1.0
5.34.0.0
5.34.1.0
5.35.0.0
5.35.1.0
5.35.2.0
5.35.3.0
5.35.4.0
5.35.5.0
5.36.0.0
5.37.0.0
5.37.1.0
5.37.1.1
5.38.0.0
5.39.0.0
5.4.0.0
5.4.1.0
5.40.0.0
5.41.0.0
5.5.0.0
5.6.0.0
5.6.1.0
5.6.2.0
5.6.2.1
5.6.3.0
5.6.4.0
5.6.5.0
5.7.1.0
5.7.2.0
5.7.3.0
5.7.4.0
5.7.5.0
5.8.0.0
5.8.1.0
5.8.2.0
5.8.3.0
5.8.4.0
5.8.5.0
5.8.5.1
5.8.6.0
5.9.0.0
6.*
6.0.0.0
6.0.1.0
6.1.0.0
6.1.0.1
6.10.0.0
6.10.1.0
6.10.2.0
6.11.0.0
6.11.1.0
6.12.0.0
6.13.0.0
6.14.0.0
6.15.0.0
6.15.0.1
6.15.1.0
6.16.0.0
6.17.0.0
6.18.0.1
6.18.1.0
6.19.0.0
6.2.0.0
6.20.0.0
6.20.0.1
6.20.0.2
6.20.0.3
6.20.1.0
6.20.2.0
6.20.2.1
6.21.0.0
6.21.1.0
6.22.0.0
6.23.0.0
6.23.1.0
6.24.0.0
6.24.1.0
6.25.0.0
6.25.1.0
6.26.0.0
6.26.1.0
6.27.0.0
6.28.0.0
6.28.1.0
6.29.0.0
6.30.0.0
6.30.1.0
6.31.0.0
6.31.1.0
6.32.0.0
6.33.0.0
6.34.0.0
6.35.0.0
6.36.0.0
6.37.0.0
6.38.0.0
6.39.0.0
6.39.1.0
6.4.0.0
6.4.1.0
6.40.0.0
6.40.1.0
6.41.0.0
6.42.0.0
6.43.0.0
6.44.0.0
6.45.0.0
6.45.1.0
6.46.0.0
6.46.1.0
6.47.0.0
6.47.1.0
6.47.2.0
6.48.0.0
6.5.0.0
6.5.1.0
6.5.2.0
6.5.3.0
6.5.4.0
6.5.5.0
6.5.5.1
6.5.6.0
6.5.6.1
6.6.0.0
6.6.0.1
6.6.1.0
6.7.0.0
6.8.0.0
6.8.1.0
6.9.0.0
6.9.1.0
6.9.2.0
v6.*
v6.3.0.0
v6.4.1.0

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-53659.json"