CVE-2026-56810
Allocation of Resources Without Limits or Throttling vulnerability in elixir-mint mint (Mint.HTTP1 module) allows a denial of service via an oversized chunked transfer-encoded response. This vulnerability is associated with program files lib/mint/http1.ex and program routines 'Elixir.Mint.HTTP1':decode_body/5, 'Elixir.Mint.HTTP1':add_body_to_buffer/2. When Mint decodes a chunked HTTP response body, it accumulates each partial fragment of the current chunk in the connection's data_buffer (an unbounded iolist) via add_body_to_buffer/2 and does not emit the data to the caller until the full declared chunk length has been received. The chunk size is taken directly from the server and parsed with no upper bound, so a malicious or compromised server can announce one enormous chunk (for example a size line of 7FFFFFFF, about 2 GiB) and then send the body bytes slowly without ever completing the chunk. The client buffers every received byte while it waits for a completion that never arrives, and because no data responses are produced until the chunk finishes, a caller that otherwise streams large content-length bodies safely gains no protection. An unauthenticated remote server (reachable whenever a client follows redirects, fetches user-supplied URLs, or processes webhooks) can drive the client's memory arbitrarily high and trigger an out-of-memory condition. This issue affects mint: from 0.5.0 before 1.9.1.
Ce que ça veut dire
- Exposition
- Exploitable à distance depuis le réseau, sans authentification et sans action de la victime.
- Impact
- Un attaquant peut mettre le service hors ligne.
- Faiblesse
- Des ressources sont allouées sans plafond : la saturation est atteignable par une simple répétition.
- Probabilité
- Le score EPSS reste bas : rien n’annonce une exploitation imminente, ce qui ne dispense pas de corriger.
À faireÀ intégrer au prochain cycle de correctifs. Commencer par les instances exposées à Internet.
Lecture automatique du vecteur CVSS, du type de faiblesse (CWE) et du score EPSS. La description technique ci-dessus reste celle publiée par le NIST, en anglais.