CVE-2026-1260725.9MediumCWE-833

CVE-2026-126072: Action Pack: Possible DoS vulnerability in Action Controller Live streaming

rails

Affected: rails · Exploitation: unlikely (under 1%)

Not in CyberSIXT coverage yet: no article names this CVE. This page shows the public record.

0.4%probability of exploitation in the next 30 days

35th percentile

050100

Higher than 35% of scored CVEs

5.9MediumCVSS 3.1

LowMediumHighCrit.

DescriptionCVE.org

Action Pack is a framework for handling and responding to web requests. Prior to 8.1.4.1 and 8.0.5.2, ActionController::Live::Buffer#close pushes its end-of-stream marker onto the response's bounded queue while it holds the buffer's monitor. When the client has stopped reading and the queue is full, the push blocks, and Buffer#abort, which runs when the client disconnects or a write times out, waits indefinitely for the same monitor. Each such response could permanently hold a web server thread and its ActionController::Live thread, possibly resulting in a DoS vulnerability through thread exhaustion. Applications that stream responses with ActionController::Live, including send_stream, are affected. Applications that serve large files through Active Storage proxy mode are exposed to unauthenticated clients. This issue is fixed in versions 8.1.4.1 and 8.0.5.2.

Affected products1

From the CVE record. A product or version that is not listed is unknown, not unaffected.

rails · rails>= 8.1, < 8.1.4.1; < 8.0.5.2

On the Atlas

Every published CVE is on the CyberSIXT Atlas, grouped by weakness, vendor and month.

Open the Atlas

Exploitation: Unlikely (under 1%). EPSS under 1%, or no score yet.
CISA KEV: Not listed
Public check: No public nuclei template
Weakness: Deadlock · Race Conditions
Vendor: rails
Published: November 2026
Band: Unlikely (under 1%), November 2026

CoverageNo articles yet

No CyberSIXT article names CVE-2026-126072 yet, so there is no coverage timeline, action brief or change log for it. Everything on this page comes from the public CVE record, CISA KEV, EPSS and the nuclei template index. Search the archive or see the CVEs in the news.