CVE-2025-61921
published 2025-10-10CVE-2025-61921: 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…
PriorityP341high7.5CVSS 3.1
AVNACLPRNUINSUCNINAH
EPSS
0.46%
37.3th percentile
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.
Affected
4 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | ruby-sinatra | < ruby-sinatra 3.0.5-3+deb12u1 (bookworm) | ruby-sinatra 3.0.5-3+deb12u1 (bookworm) |
| sinatra | sinatra | < 4.2.0 | 4.2.0 |
| sinatra | sinatra | >= 0 < 4.2.0 | 4.2.0 |
| sinatrarb | sinatra | < 4.2.0 | 4.2.0 |
CVSS provenance
nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
nvdv4.02.7LOWCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U/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
osv2.7LOW
vendor_debian2.7LOW
vendor_redhat2.7LOW
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Red Hat
sinatra: Sinatra has ReDoS vulnerability in ETag header value generation
vendor_redhat·2025-10-10·CVSS 2.7
CVE-2025-61921 [LOW] CWE-1333 sinatra: Sinatra has ReDoS vulnerability in ETag header value generation
sinatra: Sinatra has ReDoS vulnerability in ETag header value generation
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.
A flaw was found in Sinatra. A Regular Expression Denial of Servic
Debian
CVE-2025-61921: ruby-sinatra - Sinatra is a domain-specific language for creating web applications in Ruby. In ...
vendor_debian·2025·CVSS 2.7
CVE-2025-61921 [LOW] CVE-2025-61921: ruby-sinatra - Sinatra is a domain-specific language for creating web applications in Ruby. In ...
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.
Scope: local
bookworm: resolved (fixed in 3.0.5-3+deb12u1)
bullseye: open
forky: resolved (fixed in 4.2.1-1)
sid: resolved (fixed in 4.2.1-1)
GHSA
Sinatra is vulnerable to ReDoS through ETag header value generation
ghsa·2025-10-10
CVE-2025-61921 [LOW] CWE-1333 Sinatra is vulnerable to ReDoS through ETag header value generation
Sinatra is vulnerable to ReDoS through ETag header value generation
### Summary
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 and you are using Ruby = 3.2)
OSV
CVE-2025-61921: Sinatra is a domain-specific language for creating web applications in Ruby
osv·2025-10-10·CVSS 2.7
CVE-2025-61921 [LOW] CVE-2025-61921: Sinatra is a domain-specific language for creating web applications in Ruby
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.
OSV
Sinatra is vulnerable to ReDoS through ETag header value generation
osv·2025-10-10
CVE-2025-61921 [LOW] Sinatra is vulnerable to ReDoS through ETag header value generation
Sinatra is vulnerable to ReDoS through ETag header value generation
### Summary
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 and you are using Ruby = 3.2)
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2025-10-10
Published