CVE-2026-1251105.3MediumCWE-180

CVE-2026-125110: Rack: Rack::Static header_rules bypass via dot-segment normalization mismatch

rack

Affected: rack · Exploitation: unlikely (under 1%)

Not in CyberSIXT coverage yet: no article names this CVE. This page shows the public record.

0.3%probability of exploitation in the next 30 days

16th percentile

050100

Higher than 16% of scored CVEs

5.3MediumCVSS 3.1

LowMediumHighCrit.

DescriptionCVE.org

Rack is a modular Ruby web server interface. Prior to 2.2.25, 3.1.23, and 3.2.8, Rack::Static serves a path after Utils.clean_path_info normalization but evaluates header_rules against a path that is only URL-decoded. An unauthenticated attacker can request a known file through raw or percent-encoded dot segments and receive it without path-specific security headers such as Content-Disposition or Content-Security-Policy. Applications that do not use path-specific header_rules are not affected. This issue is fixed in versions 2.2.25, 3.1.23, and 3.2.8.

Affected products1

From the CVE record. A product or version that is not listed is unknown, not unaffected.

rack · rack< 2.2.25; >= 3.0, < 3.1.23; >= 3.2, < 3.2.8

On the Atlas

Every published CVE is on the CyberSIXT Atlas, grouped by weakness, vendor and month.

Open the Atlas

Exploitation: Unlikely (under 1%). EPSS under 1%, or no score yet.
CISA KEV: Not listed
Public check: No public nuclei template
Weakness: Incorrect Behavior Order: Validate Before Canonicalize · Input Validation and Logic
Vendor: rack
Published: November 2026
Band: Unlikely (under 1%), November 2026

CoverageNo articles yet

No CyberSIXT article names CVE-2026-125110 yet, so there is no coverage timeline, action brief or change log for it. Everything on this page comes from the public CVE record, CISA KEV, EPSS and the nuclei template index. Search the archive or see the CVEs in the news.