CVE-2026-124040
High
Description
CivetWeb through 1.16, when built with USE_HTTP2 and enable_http2 on, contains a use-after-free vulnerability in handle_http2() that retains freed :method and :path pointers. Unauthenticated remote attackers can send a later HEADERS frame omitting these pseudo-headers to influence request method or path seen by access rules, or crash the server.
SeverityHigh
CVSS8.1
Exploit probability—
ProductCivetweb
PublishedNov 6, 2026
First seenNov 6, 2026
Weakness typeCWE-416Use after free
How to fix
Sources list no fixed version or patch link for this vulnerability.
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| civetweb civetweb | v ≤ 1.16 | — |
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