CVE-2026-69206
Http4s is a Scala interface for HTTP services. Prior to 0.23.35 and 1.0.0-M47, DigestAuth replay protection records lastNc plus one instead of the highest nonce-count value it has accepted. When a legitimate client sends noncontiguous nc values because of parallel or retried requests, the stored counter remains below the accepted maximum, allowing a passive observer to replay a captured Authorization header multiple times. Successful replays execute authenticated requests, including state-changing operations, as the captured user. This issue is fixed in versions 0.23.35 and 1.0.0-M47.
CVSS
- Version: 3.1
- Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
- Base score: 5.9
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 0.40%
- Percentile among all scored CVEs: 31
- Score date: 10/5/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
Affected technologies (1)
⚠ AI-inferred from the description — NVD hasn't analyzed this CVE yet, these aren't verified CPEs.
CWEs
- CWE-294
References
Raw JSON (NVD)
Show
{
"id": "CVE-2026-69206",
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"version": "2.0.3",
"timestamp": "2026-09-16T17:44:48.301455Z"
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"integrityImpact": "HIGH",
"userInteraction": "NONE",
"attackComplexity": "HIGH",
"availabilityImpact": "NONE",
"privilegesRequired": "NONE",
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"published": "2026-09-15T20:17:40.180",
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"value": "Http4s is a Scala interface for HTTP services. Prior to 0.23.35 and 1.0.0-M47, DigestAuth replay protection records lastNc plus one instead of the highest nonce-count value it has accepted. When a legitimate client sends noncontiguous nc values because of parallel or retried requests, the stored counter remains below the accepted maximum, allowing a passive observer to replay a captured Authorization header multiple times. Successful replays execute authenticated requests, including state-changing operations, as the captured user. This issue is fixed in versions 0.23.35 and 1.0.0-M47."
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"lastModified": "2026-09-16T20:39:16.610",
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