CVE-2026-53659 http4k: Unbounded gzip decompression in `ServerFilters.GZip` / `RequestFilters.GunZip` allowed memory-exhaustion DoS

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...

CVE-2026-53659 http4k: Unbounded gzip decompression in `ServerFilters.GZip` / `RequestFilters.GunZip` allowed memory-exhaustion DoS

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...

EUVD-2026-77694

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...

CVE-2026-53659 http4k: Unbounded gzip decompression in `ServerFilters.GZip` / `RequestFilters.GunZip` allowed memory-exhaustion DoS

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...

CVE-2026-53659: Improper Handling of Highly Compressed Data (Data Amplification)

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...

URI Validation Bypass

http4k-security-digest is vulnerable to URI Validation Bypass. The vulnerability is due to the client not validating the uri parameter in the Digest authentication response against the actual request URL, which allows an attacker to replay a captured authentication response against other URLs...

GHSA-P28P-J94Q-PG32 http4k: `DigestAuthProvider.verify` did not bind to request URI

Impact An issue in DigestAuthProvider.verify: The uri parameter in the client's Authorization: Digest … response was not checked against the actual request URL. A captured Digest authentication response could be replayed against any other URL served by the same realm, breaking the per-request-URL...

http4k: `DigestAuthProvider.verify` did not bind to request URI

Impact An issue in DigestAuthProvider.verify: The uri parameter in the client's Authorization: Digest … response was not checked against the actual request URL. A captured Digest authentication response could be replayed against any other URL served by the same realm, breaking the per-request-URL...

GHSA-VXXM-WWQH-MH47 http4k: `DigestAuthProvider.verify` ignored configured algorithm and did not bind to request URI

Impact An issue in DigestAuthProvider.verify: Algorithm silently forced to MD5. The configured algorithm parameter was ignored — every verification used MD5 regardless of configuration. Deployments believing they were running SHA-256 Digest auth were silently inheriting MD5's collision weaknesses...

http4k: `DigestAuthProvider.verify` ignored configured algorithm and did not bind to request URI

Impact An issue in DigestAuthProvider.verify: Algorithm silently forced to MD5. The configured algorithm parameter was ignored — every verification used MD5 regardless of configuration. Deployments believing they were running SHA-256 Digest auth were silently inheriting MD5's collision weaknesses...

http4k: Unbounded gzip decompression in `ServerFilters.GZip` / `RequestFilters.GunZip` allowed memory-exhaustion DoS

Impact ServerFilters.GZip and RequestFilters.GunZip and the underlying Gzip functions used to decompress request bodies did not impose any cap on the decompressed size. A small malicious gzip-encoded request body on the order of kilobytes could decompress to gigabytes, exhausting the JVM heap and...

Improper Handling of Highly Compressed Data (Data Amplification)

Overview Affected versions of this package are vulnerable to Improper Handling of Highly Compressed Data Data Amplification through the Body.gunzipped and Body.gunzippedStream paths in core/core/src/main/kotlin/org/http4k/filter/Gzip.kt and the RequestFilters.GunZip request filter in...

GHSA-G4W2-6H2R-3M3W http4k: Unbounded gzip decompression in `ServerFilters.GZip` / `RequestFilters.GunZip` allowed memory-exhaustion DoS

Impact ServerFilters.GZip and RequestFilters.GunZip and the underlying Gzip functions used to decompress request bodies did not impose any cap on the decompressed size. A small malicious gzip-encoded request body on the order of kilobytes could decompress to gigabytes, exhausting the JVM heap and...

PT-2026-76889

Impact ServerFilters.GZip and RequestFilters.GunZip and the underlying Gzip functions used to decompress request bodies did not impose any cap on the decompressed size. A small malicious gzip-encoded request body on the order of kilobytes could decompress to gigabytes, exhausting the JVM heap and...

PT-2026-76892

Name of the Vulnerable Software and Affected Versions http4k versions prior to 4.51.0.0 http4k versions prior to 5.42.0.0 http4k versions prior to 6.50.0.0 Description In the http4k-security-digest module, the DigestAuthProvider.verify function fails to compare the uri parameter within an...

PT-2026-76891

Name of the Vulnerable Software and Affected Versions http4k versions prior to 4.51.0.0 http4k versions prior to 5.42.0.0 http4k versions prior to 6.50.0.0 Description In the http4k-security-digest module, the DigestAuthProvider.verify function ignores the configured algorithm parameter and inste...

EUVD-2024-3444

Malicious code in bioql PyPI...

CVE-2024-55875

http4k is a functional toolkit for Kotlin HTTP applications. Prior to version 6.50.0.0, there is a potential XXE XML External Entity Injection vulnerability when http4k handling malicious XML contents within requests, which might allow attackers to read local sensitive information on server,...

The vulnerability of the Kotlin HTTP http4k application library’s functionality is related to incorrect restrictions on XML links to external objects, allowing attackers to perform XXE attacks.

The vulnerability of the Kotlin HTTP http4k application’s toolset is related to incorrect restrictions on XML links to external objects. Exploiting this vulnerability allows a remote attacker to perform XXE attacks...

XML External Entity

org.http4k, http4k-format-xml is vulnerable to XML External Entity XXE Injection. The vulnerability is due to improper handling of malicious XML content in requests, which could allow attackers to access sensitive local information, perform Server-side Request Forgery SSRF, or potentially execute...