Http4s up to 0.23.34/1.0.0-M46 DigestAuth Middleware resource consumption

Summaryinfo

A vulnerability has been found in Http4s up to 0.23.34/1.0.0-M46 and classified as problematic. This vulnerability affects unknown code of the component DigestAuth Middleware. The manipulation leads to resource consumption. This vulnerability is documented as CVE-2026-69208. The attack can be initiated remotely. There is not any exploit available. The affected component should be upgraded.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in Http4s up to 0.23.34/1.0.0-M46. This issue affects an unknown part of the component DigestAuth Middleware. The manipulation with an unknown input leads to a resource consumption vulnerability. Using CWE to declare the problem leads to CWE-400. The product does not properly control the allocation and maintenance of a limited resource, thereby enabling an actor to influence the amount of resources consumed, eventually leading to the exhaustion of available resources. Impacted is availability. The summary by CVE is:

Http4s is a Scala interface for HTTP services. Prior to 0.23.35 and 1.0.0-M47, the DigestAuth server middleware removes fresh nonces and stops eviction at the first stale nonce because its stale-nonce comparison is inverted. On an application that protects at least one route with DigestAuth, an unauthenticated attacker can repeatedly trigger authentication challenges, causing the persistent nonce map to grow until the JVM exhausts heap memory. This issue is fixed in versions 0.23.35 and 1.0.0-M47.

The advisory is shared at github.com. The identification of this vulnerability is CVE-2026-69208 since 08/03/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1499 for this issue.

Upgrading to version 0.23.35 or 1.0.0-M47 eliminates this vulnerability.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Name

• Http4s

Version

• 0.23.0
• 0.23.1
• 0.23.2
• 0.23.3
• 0.23.4
• 0.23.5
• 0.23.6
• 0.23.7
• 0.23.8
• 0.23.9
• 0.23.10
• 0.23.11
• 0.23.12
• 0.23.13
• 0.23.14
• 0.23.15
• 0.23.16
• 0.23.17
• 0.23.18
• 0.23.19
• 0.23.20
• 0.23.21
• 0.23.22
• 0.23.23
• 0.23.24
• 0.23.25
• 0.23.26
• 0.23.27
• 0.23.28
• 0.23.29
• 0.23.30
• 0.23.31
• 0.23.32
• 0.23.33
• 0.23.34
• 1.0.0-M46

Website

• Product: https://github.com/http4s/http4s/

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Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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