ruby-sinatra — security advisory
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.
- Products
- ruby-sinatra
- Affected versions
- 3.0.5-3, 4.1.1-5, 4.1.1-6, 4.2.1-1, 4.2.1-2, 4.2.1-3, 4.2.1-4, 4.2.1-5
- Fixed versions
- 3.0.5-3+deb12u1, 4.2.1-1
- CVEs
- CVE-2025-61921
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 23:00 UTC · Revision 1
Source evidence
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:DEBIAN-CVE-2025-61921
ruby-sinatra
Fixed versions: 3.0.5-3+deb12u1
ruby-sinatra
Fixed versions: Not specified
ruby-sinatra
Fixed versions: 4.2.1-1
Complete source record
{
"id": "f51cdf1915b25e30e93eb36a76adce31c31cbd8a193ae3170056abfb3215d300",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2025-61921",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2025-61921",
"summary": "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.",
"evidence": "osv:DEBIAN-CVE-2025-61921",
"products": [
{
"name": {
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"evidence": "/affected/0/package/name"
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{
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"severity": "high",
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"aliases": [
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"metrics": [
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"affected": [
{
"ranges": [
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"type": "ECOSYSTEM",
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"package": {
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"ecosystem": "Debian:12"
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"versions": [
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{
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"package": {
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"purl": "pkg:deb/debian/ruby-sinatra?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"versions": [
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"4.2.1-1",
"4.2.1-2",
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],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2025-61921.json"
},
"ecosystem_specific": {
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},
{
"ranges": [
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"package": {
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"ecosystem": "Debian:14"
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"versions": [
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"database_specific": {
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}
}
],
"modified": "2026-10-23T17:47:32.516229901Z",
"provider": "osv",
"upstream": [
"CVE-2025-61921"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2025-61921"
]
},
"related_cves": [
{
"value": "CVE-2025-61921",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 417518,
"published_at": "2025-10-10T20:15:38.067+00:00"
}