CVE-2026-66835: httpd mod_auth directory protection bypassed by a doubled slash in the request path
CSIRTS triage
- What
- HTTP directory protection in httpd mod_auth is bypassed by doubling the slash in the request path.
- Who is affected
- Deployments of Erlang/OTP inets httpd with mod_auth directory protections relying on path matching.
- Urgency
- High urgency as a simple path manipulation bypasses access controls.
- Action
- Update Erlang/OTP to a patched version addressing CVE-2026-66835.
AI-assisted analysis generated from the source advisory — verify against the original.
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Details
Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-66835
Exploitation outlook
EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.
- Low exploitation riskCVE-2026-668350.64% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 48% of all EPSS-scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2026-66835 | coverage & exploitation status | NVD · CVE.org |
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