CVE-2026-26962 | Rack up to 3.2.5 HTTP Response Header Rack::Multipart crlf injection

VDB-354957 · CVE-2026-26962 · GCVE-0-2026-26962 RACK UP TO 3.2.5 HTTP RESPONSE HEADER RACK::MULTIPART CRLF INJECTION HISTORYDIFFRELATEJSONXMLCTI CVSS Meta Temp Score Current Exploit Price (≈) CTI Interest Score 4.2 $0-$5k 0.51+ Summaryinfo A vulnerability, which was classified as problematic, has been found in Rack up to 3.2.5. This impacts the function Rack::Multipart of the component HTTP Response Header Handler. Performing a manipulation results in crlf injection. This vulnerability is reported as CVE-2026-26962. The attack is possible to be carried out remotely. No exploit exists. It is advisable to upgrade the affected component. Detailsinfo A vulnerability was found in Rack up to 3.2.5. It has been classified as problematic. This affects the function Rack::Multipart of the component HTTP Response Header Handler. The manipulation with an unknown input leads to a crlf injection vulnerability. CWE is classifying the issue as CWE-93. The product uses CRLF (carriage return line feeds) as a special element, e.g. to separate lines or records, but it does not neutralize or incorrectly neutralizes CRLF sequences from inputs. This is going to have an impact on integrity. The summary by CVE is: Rack is a modular Ruby web server interface. From version 3.2.0 to before version 3.2.6, Rack::Multipart::Parser unfolds folded multipart part headers incorrectly. When a multipart header contains an obs-fold sequence, Rack preserves the embedded CRLF in parsed parameter values such as filename or name instead of removing the folded line break during unfolding. As a result, applications that later reuse those parsed values in HTTP response headers may be vulnerable to downstream header injection or response splitting. This issue has been patched in version 3.2.6. The advisory is shared at github.com. This vulnerability is uniquely identified as CVE-2026-26962 since 02/16/2026. The exploitability is told to be difficult. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Technical details are known, but no exploit is available. Upgrading to version 3.2.6 eliminates this vulnerability. Productinfo Name Rack Version 3.2.0 3.2.1 3.2.2 3.2.3 3.2.4 3.2.5 Website Product: https://github.com/rack/rack/ CPE 2.3info 🔒 🔒 🔒 CPE 2.2info 🔒 🔒 🔒 CVSSv4info VulDB Vector: 🔒 VulDB Reliability: 🔍 CVSSv3info VulDB Meta Base Score: 4.2 VulDB Meta Temp Score: 4.2 VulDB Base Score: 3.7 VulDB Temp Score: 3.6 VulDB Vector: 🔒 VulDB Reliability: 🔍 CNA Base Score: 4.8 CNA Vector (GitHub_M): 🔒 CVSSv2info Vector Complexity Authentication Confidentiality Integrity Availability Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock VulDB Base Score: 🔒 VulDB Temp Score: 🔒 VulDB Reliability: 🔍 Exploitinginfo Class: Crlf injection CWE: CWE-93 / CWE-74 / CWE-707 CAPEC: 🔒 ATT&CK: 🔒 Physical: No Local: No Remote: Yes Availability: 🔒 Status: Not defined Price Prediction: 🔍 Current Price Estimation: 🔒 0-Day Unlock Unlock Unlock Unlock Today Unlock Unlock Unlock Unlock Threat Intelligenceinfo Interest: 🔍 Active Actors: 🔍 Active APT Groups: 🔍 Countermeasuresinfo Recommended: Upgrade Status: 🔍 0-Day Time: 🔒 Upgrade: Rack 3.2.6 Timelineinfo 02/16/2026 CVE reserved 04/02/2026 +44 days Advisory disclosed 04/02/2026 +0 days VulDB entry created 04/02/2026 +0 days VulDB entry last update Sourcesinfo Product: github.com Advisory: github.com Status: Confirmed CVE: CVE-2026-26962 (🔒) GCVE (CVE): GCVE-0-2026-26962 GCVE (VulDB): GCVE-100-354957 Entryinfo Created: 04/02/2026 19:36 Changes: 04/02/2026 19:36 (64) Complete: 🔍 Cache ID: 99:226:101 Discussion No comments yet. Languages: en. Please log in to comment. ◂ PreviousOverviewNext ▸