CVE-2026-59246

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Source
https://cve.org/CVERecord?id=CVE-2026-59246
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-59246.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-59246
Aliases
Published
2026-07-14T08:37:04.609Z
Modified
2026-07-19T03:46:50.514105584Z
Severity
  • 6.3 (Medium) CVSS_V4 - CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N CVSS Calculator
Summary
Zero-length HTTP/2 CONTINUATION frames bypass Mint's header-block byte-size cap and exhaust client memory
Details

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.handlecontinuation/3 function in lib/mint/http2.ex accumulates the header-block fragment carried by each HTTP/2 CONTINUATION frame into a growing conn.headersbeingprocessed nesting, one level deeper per frame, and only releases it when a frame with the ENDHEADERS flag arrives. The only guard on this accumulator is Mint.HTTP2.assertheaderblockwithinmaxsize/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 ENDHEADERS, 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.

Database specific 
{
    "cwe_ids": [
        "CWE-770"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/59xxx/CVE-2026-59246.json",
    "unresolved_ranges": [
        {
            "extracted_events": [
                {
                    "introduced": "596ca4304504be68939c4929e0831557097962b8"
                },
                {
                    "fixed": "5779de1666344b32aefc4354184ea07f902f73ce"
                }
            ],
            "source": "AFFECTED_FIELD"
        }
    ],
    "cna_assigner": "EEF"
}
References

Affected packages

Git / github.com/elixir-mint/mint

Affected ranges

Type
GIT
Repo
https://github.com/elixir-mint/mint
Events
Introduced
47889857fb36f07606ad9c2e52080d202d419058
Fixed
d066c6685dca58fceb2e22e97a9266866b622bfc
Fixed
5779de1666344b32aefc4354184ea07f902f73ce
Database specific 
{
    "extracted_events": [
        {
            "introduced": "0.1.0"
        },
        {
            "fixed": "1.9.2"
        }
    ],
    "source": [
        "DESCRIPTION",
        "REFERENCES"
    ]
}

Affected versions

v0.*
v0.1.0
v0.2.0
v0.2.1
v0.4.0
v0.5.0
v1.*
v1.0.0
v1.1.0
v1.2.0
v1.2.1
v1.3.0
v1.4.0
v1.4.1
v1.4.2
v1.5.0
v1.5.1
v1.5.2
v1.6.0
v1.6.1
v1.6.2
v1.7.0
v1.7.1
v1.8.0
v1.9.0
v1.9.1

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-59246.json"