CVE-2021-42697
Akka HTTP 10.1.x before 10.1.15 and 10.2.x before 10.2.7 can encounter stack exhaustion while parsing HTTP headers, which allows a remote attacker to conduct a Denial of Service attack by sending a User-Agent header with deeply nested comments.
Vulnerability Summary
CVSS v3 Score
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS Score (Exploitation Probability)
This vulnerability has a 75.54% probability of being exploited in the next 30 days, ranking higher than 99% of all scored CVEs.
Related Vulnerabilities
Similar SeverityHIGH
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OpenClaw before 2026.4.22 contains an exec allowlist analysis vulnerability allowing shell expansion hiding in unquoted heredoc bodies. Attackers can bypass allowlist validation by embedding shell expansion tokens in heredoc bodies to execute unapproved commands at runtime.
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