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TI-2026-48552 Aliases CVE-2026-69208GHSA-fm4g-76c9-7w69

Http4s: DigestAuth nonce map grows unbounded

Priority MEDIUM 40CWE-400Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-400.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00766 55th percentileScored 2026-11-07
Fix Fixed http4s (http4s): 0.23.35, 1.0.0-M47org.http4s:http4s-ember-server_2.12 (Maven): 0.23.35+2 more products

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
http4shttp4sbefore 0.23.35; 1.0.0-M1 to before 1.0.0-M470.23.35, 1.0.0-M47Patch availableCNA
—org.http4s:http4s-ember-server_2.12 (Maven)before 0.23.350.23.35Patch availableGHSA-fm4g-76c9-7w69
—org.http4s:http4s-ember-server_2.13 (Maven)before 0.23.350.23.35Patch availableGHSA-fm4g-76c9-7w69
—org.http4s:http4s-ember-server_3 (Maven)before 0.23.350.23.35Patch availableGHSA-fm4g-76c9-7w69
—org.http4s:http4s-ember-server_2.13 (Maven)1.0.0-M1 to before 1.0.0-M471.0.0-M47Patch availableGHSA-fm4g-76c9-7w69
—org.http4s:http4s-ember-server_3 (Maven)1.0.0-M1 to before 1.0.0-M471.0.0-M47Patch availableGHSA-fm4g-76c9-7w69
  • http4s Vendorhttp4s Affected before 0.23.35; 1.0.0-M1 to before 1.0.0-M47 Fixed in 0.23.35, 1.0.0-M47 Patch available CNA
  • org.http4s:http4s-ember-server_2.12 (Maven) Vendor— Affected before 0.23.35 Fixed in 0.23.35 Patch available GHSA-fm4g-76c9-7w69
  • org.http4s:http4s-ember-server_2.13 (Maven) Vendor— Affected before 0.23.35 Fixed in 0.23.35 Patch available GHSA-fm4g-76c9-7w69
  • org.http4s:http4s-ember-server_3 (Maven) Vendor— Affected before 0.23.35 Fixed in 0.23.35 Patch available GHSA-fm4g-76c9-7w69
  • org.http4s:http4s-ember-server_2.13 (Maven) Vendor— Affected 1.0.0-M1 to before 1.0.0-M47 Fixed in 1.0.0-M47 Patch available GHSA-fm4g-76c9-7w69
  • org.http4s:http4s-ember-server_3 (Maven) Vendor— Affected 1.0.0-M1 to before 1.0.0-M47 Fixed in 1.0.0-M47 Patch available GHSA-fm4g-76c9-7w69

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:a:typelevel:http4s:*:*:*:*:*:*:*:*——http4s
  • cpe:2.3:a:typelevel:http4s:*:*:*:*:*:*:*:* Versions — — ·http4s

Remediation

  • Fix · CNA http4s (http4s) Fixed in 0.23.35, 1.0.0-M47
  • Fix · GHSA-fm4g-76c9-7w69 org.http4s:http4s-ember-server_2.12 (Maven) Fixed in 0.23.35 Advisory →
  • Fix · GHSA-fm4g-76c9-7w69 org.http4s:http4s-ember-server_2.13 (Maven) Fixed in 0.23.35 Advisory →
  • Fix · GHSA-fm4g-76c9-7w69 org.http4s:http4s-ember-server_3 (Maven) Fixed in 0.23.35 Advisory →
  • Fix · GHSA-fm4g-76c9-7w69 org.http4s:http4s-ember-server_2.13 (Maven) Fixed in 1.0.0-M47 Advisory →
  • Fix · GHSA-fm4g-76c9-7w69 org.http4s:http4s-ember-server_3 (Maven) Fixed in 1.0.0-M47 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-69208
  2. 2026-10-03 Alias added: GHSA-fm4g-76c9-7w69

References

Other 5

  • TI-2022-13223 mTLS client verification is skipped in fs2 on Node.js CVSS 3.1CRITICAL 9.8
  • TI-2023-08714 Http4s has fatal error parsing User-Agent and Server headers CVSS 3.1HIGH 7.5
  • TI-2022-06031 Hash collision in typelevel jawn CVSS 3.1HIGH 7.5
  • TI-2025-37261 Http4s vulnerable to HTTP Request Smuggling due to improper handling of HTTP trailer section CVSS 4.0MEDIUM 6.3
  • TI-2026-44185 http4s-scala-xml has an XML External Entity (XXE) processing issue CVSS 3.1CRITICAL 9.3
  • TI-2020-04336 Local file inclusion vulnerability in http4s CVSS 3.1HIGH 7.6
See all 36 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences