CVE-2026-34786

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Source
https://cve.org/CVERecord?id=CVE-2026-34786
Import Source
https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-34786.json
JSON Data
https://api.test.osv.dev/v1/vulns/CVE-2026-34786
Aliases
Downstream
Related
Published
2026-04-02T16:44:59.694Z
Modified
2026-04-06T00:44:19.221340216Z
Severity
  • 5.3 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N CVSS Calculator
Summary
Rack: Rack::Static header_rules bypass via URL-encoded paths
Details

Rack is a modular Ruby web server interface. Prior to versions 2.2.23, 3.1.21, and 3.2.6, Rack::Static#applicablerules evaluates several headerrules types against the raw URL-encoded PATHINFO, while the underlying file-serving path is decoded before the file is served. As a result, a request for a URL-encoded variant of a static path can serve the same file without the headers that headerrules were intended to apply. In deployments that rely on Rack::Static to attach security-relevant response headers to static content, this can allow an attacker to bypass those headers by requesting an encoded form of the path. This issue has been patched in versions 2.2.23, 3.1.21, and 3.2.6.

Database specific 
{
    "cwe_ids": [
        "CWE-180"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/34xxx/CVE-2026-34786.json",
    "cna_assigner": "GitHub_M"
}
References

Affected packages

Git / github.com/rack/rack

Affected ranges

Type
GIT
Repo
https://github.com/rack/rack
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Fixed
f2af0c8f869193fa7bb7d20b619b3003418e1055
Database specific 
{
    "versions": [
        {
            "introduced": "0"
        },
        {
            "fixed": "2.2.23"
        }
    ]
}
Type
GIT
Repo
https://github.com/rack/rack
Events
Introduced
572a42a705b423ce98ef4e81435d4f60fb0ae53d
Fixed
ae8431120e66e92d1885ab8ec0a553d9cad5ec13
Database specific 
{
    "versions": [
        {
            "introduced": "3.0.0.beta1"
        },
        {
            "fixed": "3.1.21"
        }
    ]
}
Type
GIT
Repo
https://github.com/rack/rack
Events
Introduced
b68251c03788ff39d4a4b25424df7360426e4afd
Fixed
e1f22fdbe99afd2126b6fbf05bb12399359574b7
Database specific 
{
    "versions": [
        {
            "introduced": "3.2.0"
        },
        {
            "fixed": "3.2.6"
        }
    ]
}

Affected versions

0.*
0.1
0.2
0.3
0.4
0.9
0.9.1
1.*
1.0
1.0.1
1.1
1.1.2
1.1.3
1.1.4
1.1.5
1.1.6
1.2
1.2.1
1.2.2
1.2.3
1.2.4
1.2.5
1.2.6
1.2.7
1.2.8
1.3.0
1.3.0.beta
1.3.0.beta2
1.3.1
1.3.10
1.3.2
1.3.3
1.3.4
1.3.5
1.3.6
1.3.7
1.3.8
1.3.9
1.4.0
1.4.1
1.4.2
1.4.3
1.4.4
1.4.5
1.4.6
1.4.7
1.5.0
1.5.1
1.5.2
1.5.3
1.5.4
1.5.5
1.6.0
1.6.0.beta
1.6.0.beta2
1.6.1
1.6.10
1.6.11
1.6.12
1.6.13
1.6.2
1.6.3
1.6.4
1.6.5
1.6.6
1.6.7
1.6.8
1.6.9
2.*
2.0.0
2.0.0.alpha
2.0.0.rc1
2.0.1
2.0.2
2.0.3
2.0.4
2.0.5
2.0.6
2.0.7
2.0.8
2.0.9
2.0.9.1
2.1.0
2.1.1
2.1.2
2.1.3
2.1.4
2.1.4.1
2.2.0
2.2.3
2.2.3.1
2.2.4
3.*
3.0.0
3.0.0.beta1
3.0.0.rc1
Other
test
v2.*
v2.0.9.2
v2.0.9.3
v2.0.9.4
v2.1.4.2
v2.1.4.3
v2.1.4.4
v2.2.1
v2.2.10
v2.2.11
v2.2.12
v2.2.13
v2.2.14
v2.2.15
v2.2.16
v2.2.17
v2.2.18
v2.2.19
v2.2.2
v2.2.20
v2.2.21
v2.2.22
v2.2.5
v2.2.6
v2.2.6.1
v2.2.6.2
v2.2.6.3
v2.2.6.4
v2.2.7
v2.2.8
v2.2.8.1
v2.2.9
v3.*
v3.0.1
v3.0.10
v3.0.12
v3.0.13
v3.0.14
v3.0.15
v3.0.16
v3.0.17
v3.0.18
v3.0.2
v3.0.3
v3.0.4
v3.0.4.1
v3.0.4.2
v3.0.5
v3.0.6
v3.0.6.1
v3.0.7
v3.0.8
v3.0.9
v3.0.9.1
v3.1.0
v3.1.1
v3.1.10
v3.1.11
v3.1.12
v3.1.13
v3.1.14
v3.1.15
v3.1.16
v3.1.17
v3.1.18
v3.1.19
v3.1.2
v3.1.20
v3.1.21
v3.1.3
v3.1.4
v3.1.5
v3.1.6
v3.1.7
v3.1.8
v3.1.9
v3.2.0
v3.2.1
v3.2.2
v3.2.3
v3.2.4
v3.2.5
v3.2.6

Database specific

source 
"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-34786.json"