CVE-2026-39806
Essential information
- Published
- 13/05/2026 14:17
- Modified
- 13/05/2026 16:16
- Author
- —
- Creator
- —
- CVSS
- 8.7 HIGH (v3) 8.7 HIGH (v4.0)
- CISA KEV
- No
- CWE
- —
- CVSS vector
-
—
—
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CVSS metrics
- Access vector
- —
- Access complexity
- —
- Authentication
- —
- Confidentiality impact
- —
- Integrity impact
- —
- Availability impact
- —
- Exploitability
- —
- Remediation level
- —
- Report confidence
- —
- Temporal score
- —
- Attack vector
- —
- Attack complexity
- —
- Privileges required
- —
- User interaction
- —
- Scope
- —
- Confidentiality impact
- —
- Integrity impact
- —
- Availability impact
- —
- Exploit code maturity
- —
- Remediation level
- —
- Report confidence
- —
- Temporal score
- —
- Attack vector
- NETWORK
- Attack complexity
- LOW
- Attack requirements
- NONE
- Privileges required
- NONE
- User interaction
- NONE
- Confidentiality (V)
- NONE
- Confidentiality (S)
- NONE
- Integrity (V)
- NONE
- Integrity (S)
- NONE
- Availability (V)
- HIGH
- Availability (S)
- NONE
- Exploit maturity
- NOT_DEFINED
Description
Loop with Unreachable Exit Condition ('Infinite Loop') vulnerability in mtrudel bandit allows unauthenticated remote denial of service via worker process exhaustion.
'Elixir.Bandit.HTTP1.Socket':do_read_chunked_data!/5 in lib/bandit/http1/socket.ex terminates only when the last-chunk line 0\r\n is followed immediately by the empty trailer line \r\n. RFC 9112 §7.1.2 permits zero or more trailer fields between them. When trailers are present, none of the match clauses fit: the catch-all arm computes a negative to_read, calls read_available!/2, receives <<>> on timeout, and tail-recurses with unchanged state. The worker process is pinned for the lifetime of the TCP connection.
A handful of concurrent connections sending RFC-conformant chunked requests with trailer fields is sufficient to exhaust the Bandit worker pool and render the server unresponsive to all further traffic. No authentication, special headers, or large payload is required. Proxies such as NGINX and HAProxy legitimately forward trailer-bearing requests, so servers behind such proxies may be affected without any malicious client involvement.
This issue affects bandit: from 1.6.1 before 1.11.1.
NVD status
- Status
- Awaiting Analysis — CVE has been marked for Analysis. Normally once in this state the CVE will be analyzed by NVD staff within 24 hours.
- Source
- 6b3ad84c-e1a6-4bf7-a703-f496b71e49db
- NVD
- View on NVD
Affected products (CPE)
| Product | CPE |
|---|---|
| bandit / bandit | cpe:2.3:a:bandit:bandit:<1.11.1:*:*:*:*:*:*:* |