DEBIAN-CVE-2025-61921
Record from OSV · Published October 10, 2025
Sinatra is a domain-specific language for creating web applications in Ruby. In versions prior to 4.2.0, there is a denial of service vulnerability in the `If-Match` and `If-None-Match` header parsing component of Sinatra, if the `etag` method is used when constructing the response. Carefully crafted input can cause `If-Match` and `If-None-Match` header parsing in Sinatra to take an unexpected amount of time, possibly resulting in a denial of service attack vector. This header is typically involved in generating the `ETag` header value. Any applications that use the `etag` method when generating a response are impacted. Version 4.2.0 fixes the issue.
Fixed versions
Upgrade to a fixed version or later. Language registries are listed first, then Linux distributions, then vendor products.
| Package | Ecosystem | Fixed in |
|---|---|---|
| ruby-sinatra | Debian:14 | 4.2.1-1 |
| ruby-sinatra | Debian:12 | 3.0.5-3+deb12u1 |
Risk scores
Affected products
| Vendor | Product | Versions |
|---|---|---|
| Debian:14 | ruby-sinatra | 4.1.1-6, 0, 4.1.1-5 |
| Debian:12 | ruby-sinatra | 3.0.5-3, 0 |
| Debian:13 | ruby-sinatra | 4.2.1-2, 4.2.1-3, 4.2.1-4 |
Timeline
- Oct 10, 2025 CVE Published
- Oct 23, 2026 CVE Updated
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