Bandit: Unauthenticated one-shot DoS via `Transfer-Encoding: chunked`

Summary Bandit's HTTP/1 chunked-body reader silently drops the request size cap that the application configures e.g. Plug.Parsers' default 8 MB length: and buffers the entire body in memory before the application sees it. An unauthenticated attacker can crash any Bandit-fronted Phoenix/Plug app...

GHSA-9Q9Q-324X-93R2 Bandit: Unauthenticated one-shot DoS via `Transfer-Encoding: chunked`

Summary Bandit's HTTP/1 chunked-body reader silently drops the request size cap that the application configures e.g. Plug.Parsers' default 8 MB length: and buffers the entire body in memory before the application sees it. An unauthenticated attacker can crash any Bandit-fronted Phoenix/Plug app...

CVE-2026-42786

A flaw was found in bandit. A remote, unauthenticated attacker can exploit an Allocation of Resources Without Limits or Throttling vulnerability in the fragment reassembly path of the WebSocket connection handling. This allows the attacker to send an unbounded number of continuation frames, leadi...

CVE-2026-39805

A flaw was found in Bandit, an HTTP server. This vulnerability allows for HTTP request smuggling due to the server's inconsistent handling of duplicate Content-Length headers in HTTP requests. An unauthenticated attacker can exploit this by sending a specially crafted request. If Bandit is...

CVE-2026-39804

A flaw was found in bandit. An unauthenticated attacker who can open a WebSocket connection can exploit a vulnerability when WebSocket permessage-deflate compression is enabled. This flaw allows for memory exhaustion by sending a highly compressed frame that, when decompressed, forces large memor...

CVE-2026-39806

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':doreadchunkeddata!/5 in lib/bandit/http1/socket.ex terminates only when the last-chunk line 0\r\n is...

CVE-2026-39803

Allocation of Resources Without Limits or Throttling vulnerability in mtrudel bandit allows unauthenticated remote denial of service via memory exhaustion. The chunked clause of 'Elixir.Bandit.HTTP1.Socket':readdata/2 in lib/bandit/http1/socket.ex ignores the caller-supplied :length option when...

CVE-2026-39806

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':doreadchunkeddata!/5 in lib/bandit/http1/socket.ex terminates only when the last-chunk line 0\r\n is...

CVE-2026-39806 HTTP/1 chunked decoder infinite loop on requests with trailer fields in bandit

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':doreadchunkeddata!/5 in lib/bandit/http1/socket.ex terminates only when the last-chunk line 0\r\n is...

CVE-2026-39806 HTTP/1 chunked decoder infinite loop on requests with trailer fields in bandit

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':doreadchunkeddata!/5 in lib/bandit/http1/socket.ex terminates only when the last-chunk line 0\r\n is...

CVE-2026-39806 HTTP/1 chunked decoder infinite loop on requests with trailer fields in bandit

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':doreadchunkeddata!/5 in lib/bandit/http1/socket.ex terminates only when the last-chunk line 0\r\n is...

CVE-2026-39806

The CVE-2026-39806 issue affects Bandit (Elixir.Bandit.HTTP1.Socket) where do_read_chunked_data!/5 loops indefinitely when a chunked request includes trailer fields. The root cause is that RFC 9112 §7.1.2 allows trailers after the 0-length chunk, but the code exits only when the next line is imme...

EEF-CVE-2026-39806 HTTP/1 chunked decoder infinite loop on requests with trailer fields in bandit

Summary 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...

CVE-2026-39803 HTTP/1 chunked body reader ignores length cap in bandit

Allocation of Resources Without Limits or Throttling vulnerability in mtrudel bandit allows unauthenticated remote denial of service via memory exhaustion. The chunked clause of 'Elixir.Bandit.HTTP1.Socket':readdata/2 in lib/bandit/http1/socket.ex ignores the caller-supplied :length option when...

CVE-2026-39803

CVE-2026-39803 – Bandit (Elixir) memory exhaustion via chunked HTTP/1 bodies. The issue occurs in the chunked path of Elixir.Bandit.HTTP1.Socket.read_data/2 where the caller-supplied length is ignored; every received chunk is buffered into an iolist and the entire body is materialized as a single...

CVE-2026-39803 HTTP/1 chunked body reader ignores length cap in bandit

Allocation of Resources Without Limits or Throttling vulnerability in mtrudel bandit allows unauthenticated remote denial of service via memory exhaustion. The chunked clause of 'Elixir.Bandit.HTTP1.Socket':readdata/2 in lib/bandit/http1/socket.ex ignores the caller-supplied :length option when...

CVE-2026-39803 HTTP/1 chunked body reader ignores length cap in bandit

Allocation of Resources Without Limits or Throttling vulnerability in mtrudel bandit allows unauthenticated remote denial of service via memory exhaustion. The chunked clause of 'Elixir.Bandit.HTTP1.Socket':readdata/2 in lib/bandit/http1/socket.ex ignores the caller-supplied :length option when...

CVE-2026-39803

Allocation of Resources Without Limits or Throttling vulnerability in mtrudel bandit allows unauthenticated remote denial of service via memory exhaustion. The chunked clause of 'Elixir.Bandit.HTTP1.Socket':readdata/2 in lib/bandit/http1/socket.ex ignores the caller-supplied :length option when...

EEF-CVE-2026-39803 HTTP/1 chunked body reader ignores length cap in bandit

Summary Allocation of Resources Without Limits or Throttling vulnerability in mtrudel bandit allows unauthenticated remote denial of service via memory exhaustion. The chunked clause of 'Elixir.Bandit.HTTP1.Socket':read\data/2 in lib/bandit/http1/socket.ex ignores the caller-supplied :length opti...

PT-2026-40608

Name of the Vulnerable Software and Affected Versions bandit versions 1.6.1 through 1.11.0 Description An infinite loop in the do read chunked data!/5 function within lib/bandit/http1/socket.ex allows unauthenticated remote attackers to cause a denial of service via worker process exhaustion. The...