6.3
MEDIUM CVSS 4.0
CVE-2026-59246
Zero-length HTTP/2 CONTINUATION frames bypass Mint's header-block byte-size cap and exhaust client memory
Description

Allocation of resources without limits vulnerability in elixir-mint mint allows a remote HTTP/2 server to exhaust memory on the client host and cause a denial of service. The Mint.HTTP2.handle_continuation/3 function in lib/mint/http2.ex accumulates the header-block fragment carried by each HTTP/2 CONTINUATION frame into a growing conn.headers_being_processed nesting, one level deeper per frame, and only releases it when a frame with the END_HEADERS flag arrives. The only guard on this accumulator is Mint.HTTP2.assert_header_block_within_max_size/2, which sums the byte size of the fragments received so far. Because a CONTINUATION frame is permitted by the protocol to carry a zero-length payload, an unbounded chain of zero-length CONTINUATION frames adds no bytes to the running total, never trips the size cap, and never emits END_HEADERS, yet each frame still nests the accumulator one level deeper. A malicious HTTP/2 server (reachable directly, via an attacker-controlled redirect, via SSRF, or via a man-in-the-middle) can open a stream by sending a HEADERS frame without END_HEADERS and then stream zero-length CONTINUATION frames indefinitely. Client memory grows one cons cell per frame received; sustained bandwidth from the peer drives the BEAM node running the Mint client to memory exhaustion and eventual out-of-memory termination. This issue affects mint: from 0.1.0 before 1.9.2.

INFO

Published Date :

July 14, 2026, 9:16 a.m.

Last Modified :

July 14, 2026, 9:16 a.m.

Remotely Exploit :

Yes !

Source :

6b3ad84c-e1a6-4bf7-a703-f496b71e49db
Affected Products

The following products are affected by CVE-2026-59246 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Elixir-mint mint
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 4.0 MEDIUM 6b3ad84c-e1a6-4bf7-a703-f496b71e49db
CVSS 4.0 MEDIUM 6b3ad84c-e1a6-4bf7-a703-f496b71e49db
Solution
Update mint to version 1.9.2 or later to fix memory exhaustion via CONTINUATION frames.
  • Update the mint library to version 1.9.2 or later.
  • Apply security patches for affected systems.
  • Monitor client resource usage for DoS indicators.
References to Advisories, Solutions, and Tools
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-59246 is associated with the following CWEs:

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-59246 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-59246 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by 6b3ad84c-e1a6-4bf7-a703-f496b71e49db

    Jul. 14, 2026

    Action Type Old Value New Value
    Added Affected [{'cpes': ['cpe:2.3:a:elixir-mint:mint:*:*:*:*:*:*:*:*'], 'repo': 'https://github.com/elixir-mint/mint', 'vendor': 'elixir-mint', 'modules': ["'Elixir.Mint.HTTP2'"], 'product': 'mint', 'versions': [{'status': 'affected', 'version': '0.1.0', 'lessThan': '1.9.2', 'versionType': 'semver'}], 'packageURL': 'pkg:hex/mint', 'packageName': 'mint', 'programFiles': ['lib/mint/http2.ex'], 'collectionURL': 'https://repo.hex.pm', 'defaultStatus': 'unaffected', 'programRoutines': [{'name': "'Elixir.Mint.HTTP2':handle_continuation/3"}, {'name': "'Elixir.Mint.HTTP2':assert_header_block_within_max_size/2"}]}, {'cpes': ['cpe:2.3:a:elixir-mint:mint:*:*:*:*:*:*:*:*'], 'repo': 'https://github.com/elixir-mint/mint', 'vendor': 'elixir-mint', 'modules': ["'Elixir.Mint.HTTP2'"], 'product': 'mint', 'versions': [{'status': 'affected', 'version': '596ca4304504be68939c4929e0831557097962b8', 'lessThan': '5779de1666344b32aefc4354184ea07f902f73ce', 'versionType': 'git'}], 'packageURL': 'pkg:github/elixir-mint/mint', 'packageName': 'elixir-mint/mint', 'programFiles': ['lib/mint/http2.ex'], 'collectionURL': 'https://github.com', 'defaultStatus': 'unaffected', 'programRoutines': [{'name': "'Elixir.Mint.HTTP2':handle_continuation/3"}, {'name': "'Elixir.Mint.HTTP2':assert_header_block_within_max_size/2"}]}]
    Added Description Allocation of resources without limits vulnerability in elixir-mint mint allows a remote HTTP/2 server to exhaust memory on the client host and cause a denial of service. The Mint.HTTP2.handle_continuation/3 function in lib/mint/http2.ex accumulates the header-block fragment carried by each HTTP/2 CONTINUATION frame into a growing conn.headers_being_processed nesting, one level deeper per frame, and only releases it when a frame with the END_HEADERS flag arrives. The only guard on this accumulator is Mint.HTTP2.assert_header_block_within_max_size/2, which sums the byte size of the fragments received so far. Because a CONTINUATION frame is permitted by the protocol to carry a zero-length payload, an unbounded chain of zero-length CONTINUATION frames adds no bytes to the running total, never trips the size cap, and never emits END_HEADERS, yet each frame still nests the accumulator one level deeper. A malicious HTTP/2 server (reachable directly, via an attacker-controlled redirect, via SSRF, or via a man-in-the-middle) can open a stream by sending a HEADERS frame without END_HEADERS and then stream zero-length CONTINUATION frames indefinitely. Client memory grows one cons cell per frame received; sustained bandwidth from the peer drives the BEAM node running the Mint client to memory exhaustion and eventual out-of-memory termination. This issue affects mint: from 0.1.0 before 1.9.2.
    Added CVSS V4.0 AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/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
    Added CWE CWE-770
    Added Reference https://cna.erlef.org/cves/CVE-2026-59246.html
    Added Reference https://github.com/elixir-mint/mint/commit/5779de1666344b32aefc4354184ea07f902f73ce
    Added Reference https://github.com/elixir-mint/mint/security/advisories/GHSA-8pf6-g464-h6h9
    Added Reference https://osv.dev/vulnerability/EEF-CVE-2026-59246
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.