Answer in brief
CVE-2026-125111 records a High severity (CVSS 7.5) vulnerability in Rack: Multipart parsing allows DoS via unbounded scan buffer growth. The current sources do not mark it as known exploited. The current feed maps rack/rack (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 7.5. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps rack/rack (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| rack/rackgeneric | <2.2.25 || >=3.0 <3.1.23 || >=3.2 <3.2.8 | 2.2.25, 3.1.23, 3.2.8 |
Published upstream
Nov 9, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Nov 9, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Nov 9, 2026
Rack is a modular Ruby web server interface. Prior to 2.2.25, 3.1.23, and 3.2.8, Rack::Multipart::Parser can retain parsed data in its internal StringScanner buffer when reads end inside or immediately after multipart headers. An unauthenticated attacker can align many small parts with rack.multipart.buffer_size boundaries so the buffer grows with the request despite per-field, header, and preamble limits, causing a worker to exhaust memory. The attack requires only a well-formed multipart body and affects applications that parse multipart requests. This issue is fixed in versions 2.2.25, 3.1.23, and 3.2.8.
Quoted source text, attributed separately from HOL analysis.