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TI-2026-64972 Aliases CVE-2026-100834GHSA-r39r-ww5m-7mv9

http4k before 6.48.0.0 Digest Authentication Replay Protection Bypass

Priority LOW 36CWE-294Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
Present
Impact type
Security bypass
Confidentiality · integrity · availability
High · None · None
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-294.

Summary

http4k's Digest authentication module (org.http4k:http4k-security-digest) before versions 6.48.0.0, 5.42.0.0 and 4.51.0.0 defaults the nonceVerifier parameter of ServerFilters.DigestAuth and DigestAuthProvider to { true }, so every nonce is accepted regardless of its value, age, or prior use. Applications relying on this default have no replay protection on Digest authentication: an attacker who can capture a valid 'Authorization: Digest' response (for example by observing network traffic or reading logs) can replay it indefinitely against the same protected resource.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.0032 25th percentileScored 2026-11-07
Fix Fixed http4k (http4k): 6.48.0.0, 5.42.0.0, 4.51.0.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
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
http4khttp4k6.0.0.0 to before 6.48.0.06.48.0.0Patch availableCNA
http4khttp4k5.0.0.0 to before 5.42.0.05.42.0.0Patch availableCNA
http4khttp4kbefore 4.51.0.04.51.0.0Patch availableCNA
  • http4k Vendorhttp4k Affected 6.0.0.0 to before 6.48.0.0 Fixed in 6.48.0.0 Patch available CNA
  • http4k Vendorhttp4k Affected 5.0.0.0 to before 5.42.0.0 Fixed in 5.42.0.0 Patch available CNA
  • http4k Vendorhttp4k Affected before 4.51.0.0 Fixed in 4.51.0.0 Patch available CNA

Remediation

  • Fix · CNA http4k (http4k) Fixed in 6.48.0.0
  • Fix · CNA http4k (http4k) Fixed in 5.42.0.0
  • Fix · CNA http4k (http4k) Fixed in 4.51.0.0

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    http4k 4.51.0.0, 5.42.0.0

    3 records Highest priority Priority LOW 3 LOW

    Other records, highest priority first

    • TI-2026-64881 http4k before 6.48.0.0 Cookie Scoping Bypass via BasicCookieStoragePriority LOW 36
    • TI-2026-64880 http4k before 6.49.0.0 Host Header Routing Bypass via reverseProxyPriority LOW 28
    Show all 3 records →
  • Release ·

    http4k 6.48.0.0

    2 records Highest priority Priority LOW 2 LOW

    Other records, highest priority first

    • TI-2026-64881 http4k before 6.48.0.0 Cookie Scoping Bypass via BasicCookieStoragePriority LOW 36
    Show all 2 records →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-100834
  2. 2026-10-03 Alias added: GHSA-r39r-ww5m-7mv9
  3. 2026-10-29 Affected versions changed · CNA

References

Patch 2

Advisory 1

  • TI-2024-36944 http4k has a potential XXE (XML External Entity Injection) vulnerability CVSS 3.1CRITICAL 9.8
  • TI-2026-83683 Missing body integrity check in http4k Digest auth-int CVSS 4.0HIGH 8.2
  • TI-2026-38700 http4k: Unbounded gzip decompression in `ServerFilters.GZip` / `RequestFilters.GunZip` allowed memory-exhaustion DoS CVSS 3.1HIGH 7.5
  • TI-2026-39062 http4k: `DigestAuthProvider.verify` did not bind to request URI CVSS 3.1HIGH 8.1
  • TI-2026-64881 http4k before 6.48.0.0 Cookie Scoping Bypass via BasicCookieStorage CVSS 4.0HIGH 8.3
  • TI-2026-83682 Path traversal in http4k ThymeleafTemplates lets attackers read files CVSS 4.0HIGH 8.2
See all 8 →

Sources

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