CVE-2026-69209: Uncontrolled Resource Consumption

Http4s is a Scala interface for HTTP services. Prior to 0.23.35 and 1.0.0-M47, The shared WebSocket decoder permits unbounded message buffering because defragmentation accumulates fragments without a limit and FrameTranscoder accepts declared lengths up to Int.MaxValue. A remote client that...

HTTP Request Smuggling

Overview Affected versions of this package are vulnerable to HTTP Request Smuggling in its HTTP/1.1 wire parser http/src/main/java/org/http4s/blaze/http/parser/, which carries five independent conformance laxities, notably in Content-Length handling relative to RFC 9110 section 8.6 and RFC 9112. ...

CVE-2026-73493

Http4s http4s-blaze-server is a minimal, idiomatic Scala interface for HTTP services. Prior to 0.23.18 and 1.0.0-M42, http4s-blaze-server aggregates fragments of an incoming WebSocket message with no limit on total size or fragment count. A client that completes a WebSocket handshake can send an...

CVE-2026-73493

Summary: The CVE affects http4s-blaze-server in WebSocket handling where fragmented messages can be aggregated without an upper bound, causing unbounded heap growth and potential DoS via OutOfMemoryError on the Blaze server thread. Affected scope: any http4s application serving WebSocket routes o...

CVE-2026-73493 http4s-blaze-server: Unbounded WebSocket message aggregation

Http4s http4s-blaze-server is a minimal, idiomatic Scala interface for HTTP services. Prior to 0.23.18 and 1.0.0-M42, http4s-blaze-server aggregates fragments of an incoming WebSocket message with no limit on total size or fragment count. A client that completes a WebSocket handshake can send an...

CVE-2026-73493

Http4s http4s-blaze-server is a minimal, idiomatic Scala interface for HTTP services. Prior to 0.23.18 and 1.0.0-M42, http4s-blaze-server aggregates fragments of an incoming WebSocket message with no limit on total size or fragment count. A client that completes a WebSocket handshake can send an...

CVE-2026-73493 http4s-blaze-server: Unbounded WebSocket message aggregation

Http4s http4s-blaze-server is a minimal, idiomatic Scala interface for HTTP services. Prior to 0.23.18 and 1.0.0-M42, http4s-blaze-server aggregates fragments of an incoming WebSocket message with no limit on total size or fragment count. A client that completes a WebSocket handshake can send an...

PT-2026-71347

Name of the Vulnerable Software and Affected Versions http4s-blaze-server versions prior to 0.23.18 http4s-blaze-server versions prior to 1.0.0-M42 Description The software aggregates fragments of incoming WebSocket messages without limiting the total size or the number of fragments. A client can...

CVE-2026-73493: Allocation of Resources Without Limits or Throttling

Http4s http4s-blaze-server is a minimal, idiomatic Scala interface for HTTP services. Prior to 0.23.18 and 1.0.0-M42, http4s-blaze-server aggregates fragments of an incoming WebSocket message with no limit on total size or fragment count. A client that completes a WebSocket handshake can send an...

ch.j3t:zio-prefetcher_2.12 (>=0.3.0, <=0.8.0-rc6), com.akolov:doorman-core_2.12 (0.0.5) +148 more potentially affected by CVE-2026-73493 via org.http4s:http4s-blaze-server_2.12 (>=0.15.0a, <=1.0-234-d1a2b53)

org.http4s:http4s-blaze-server2.12 MAVEN version =0.15.0a, =0.3.0, =0.3.0, =0.18.1, =0.1.4, =0.1.4, =0.1.4, =0.1.4, =0.0.6-m4, =0.0.6-m4, =0.0.13, =0.0.13, =0.0.30 and more Source cves: CVE-2026-73493 Source advisory: SNYK:JAVA-ORGHTTP4S-18313134...

HTTP Request Smuggling

Overview Affected versions of this package are vulnerable to HTTP Request Smuggling in the process that merges HTTP/1.1 chunked-body trailer fields into Request.headers. An attacker can inject arbitrary HTTP headers by sending specially crafted trailer fields, potentially bypassing header-based...

ch.j3t:zio-prefetcher_2.12 (>=0.3.0, <=0.8.0-rc6), com.akolov:doorman-core_2.12 (0.0.5) +148 more potentially affected by CVE-2026-73495 via org.http4s:http4s-blaze-server_2.12 (>=0.15.0a, <=1.0-234-d1a2b53)

org.http4s:http4s-blaze-server2.12 MAVEN version =0.15.0a, =0.3.0, =0.3.0, =0.18.1, =0.1.4, =0.1.4, =0.1.4, =0.1.4, =0.0.6-m4, =0.0.6-m4, =0.0.13, =0.0.13, =0.0.30 and more Source cves: CVE-2026-73495 Source advisory: SNYK:JAVA-ORGHTTP4S-18313125...

ch.j3t:zio-prefetcher_2.12 (>=0.3.0, <=0.8.0-rc6), com.akolov:doorman-core_2.12 (0.0.5) +148 more potentially affected by unknown CVE via org.http4s:http4s-blaze-server_2.12 (>=0.15.0a, <=1.0-234-d1a2b53)

org.http4s:http4s-blaze-server2.12 MAVEN version =0.15.0a, =0.3.0, =0.3.0, =0.18.1, =0.1.4, =0.1.4, =0.1.4, =0.1.4, =0.0.6-m4, =0.0.6-m4, =0.0.13, =0.0.13, =0.0.30 and more Source cves: unknown CVE Source advisory: SNYK:JAVA-ORGHTTP4S-18313139...

CVE-2021-21293

blaze is a Scala library for building asynchronous pipelines, with a focus on network IO. All servers running blaze-core before version 0.14.15 are affected by a vulnerability in which unbounded connection acceptance leads to file handle exhaustion. Blaze, accepts connections unconditionally on a...

Design/Logic Flaw

blaze is a Scala library for building asynchronous pipelines, with a focus on network IO. All servers running blaze-core before version 0.14.15 are affected by a vulnerability in which unbounded connection acceptance leads to file handle exhaustion. Blaze, accepts connections unconditionally on a...

Unbounded connection acceptance leads to file handle exhaustion

Impact All servers running blaze-core = 0.14.14, including blaze-http and http4s-blaze-server users, are affected. Blaze, accepts connections unconditionally on a dedicated thread pool. This has the net effect of amplifying degradation in services that are unable to handle their current request...

GHSA-XMW9-Q7X9-J5QC Unbounded connection acceptance leads to file handle exhaustion

Impact All servers running blaze-core = 0.14.14, including blaze-http and http4s-blaze-server users, are affected. Blaze, accepts connections unconditionally on a dedicated thread pool. This has the net effect of amplifying degradation in services that are unable to handle their current request...

CVE-2021-21293 Unbounded connection acceptance leads to file handle exhaustion

blaze is a Scala library for building asynchronous pipelines, with a focus on network IO. All servers running blaze-core before version 0.14.15 are affected by a vulnerability in which unbounded connection acceptance leads to file handle exhaustion. Blaze, accepts connections unconditionally on a...

PT-2021-14395 · Unknown +1 · Blaze-Core +5

Name of the Vulnerable Software and Affected Versions: blaze-core versions prior to 0.14.15 http4s-blaze-server versions prior to 0.21.17 Description: The issue is caused by unbounded connection acceptance in blaze-core, leading to file handle exhaustion. This can amplify degradation in services...

CVE-2021-21293: Uncontrolled Resource Consumption

blaze is a Scala library for building asynchronous pipelines, with a focus on network IO. All servers running blaze-core before version 0.14.15 are affected by a vulnerability in which unbounded connection acceptance leads to file handle exhaustion. Blaze, accepts connections unconditionally on a...