CVE-2026-28755 | F5 NGINX Open Source/NGINX Plus ngx_stream_ssl_module authorization (K000160368)

VDB-352786 · CVE-2026-28755 · K000160368 F5 NGINX OPEN SOURCE/NGINX PLUS NGX_STREAM_SSL_MODULE AUTHORIZATION HISTORYDIFFRELATEJSONXMLCTI CVSS Meta Temp Score Current Exploit Price (≈) CTI Interest Score 5.7 $0-$5k 1.36+ Summaryinfo A vulnerability classified as critical was found in F5 NGINX Open Source and NGINX Plus. Impacted is the function ngx_stream_ssl_module. Executing a manipulation can lead to authorization. This vulnerability is handled as CVE-2026-28755. The attack can be executed remotely. There is not any exploit available. Upgrading the affected component is advised. Detailsinfo A vulnerability has been found in F5 NGINX Open Source and NGINX Plus (version unknown) and classified as critical. This vulnerability affects the function ngx_stream_ssl_module. The manipulation with an unknown input leads to a authorization vulnerability. The CWE definition for the vulnerability is CWE-863. The product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check. This allows attackers to bypass intended access restrictions. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes: NGINX Plus and NGINX Open Source have a vulnerability in the ngx_stream_ssl_module module due to the improper handling of revoked certificates when configured with the ssl_verify_client on and ssl_ocsp on directives, allowing the TLS handshake to succeed even after an OCSP check identifies the certificate as revoked.   Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated. The advisory is available at my.f5.com. This vulnerability was named CVE-2026-28755 since 03/18/2026. The exploitation appears to be easy. The attack can be initiated remotely. Technical details are known, but there is no available exploit. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 03/24/2026). Upgrading eliminates this vulnerability. Productinfo Type Web Server Vendor F5 Name NGINX Open Source NGINX Plus License commercial Website Vendor: https://f5.com/ CPE 2.3info 🔒 CPE 2.2info 🔒 CVSSv4info VulDB Vector: 🔒 VulDB Reliability: 🔍 CNA CVSS-B Score: 🔒 CNA CVSS-BT Score: 🔒 CNA Vector: 🔒 CVSSv3info VulDB Meta Base Score: 5.9 VulDB Meta Temp Score: 5.7 VulDB Base Score: 6.3 VulDB Temp Score: 6.0 VulDB Vector: 🔒 VulDB Reliability: 🔍 CNA Base Score: 5.4 CNA Vector: 🔒 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: Authorization CWE: CWE-863 / CWE-285 / CWE-266 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: 🔒 Timelineinfo 03/18/2026 CVE reserved 03/24/2026 +6 days Advisory disclosed 03/24/2026 +0 days VulDB entry created 03/24/2026 +0 days VulDB entry last update Sourcesinfo Vendor: f5.com Advisory: K000160368 Status: Confirmed CVE: CVE-2026-28755 (🔒) GCVE (CVE): GCVE-0-2026-28755 GCVE (VulDB): GCVE-100-352786 Entryinfo Created: 03/24/2026 16:08 Changes: 03/24/2026 16:08 (74) Complete: 🔍 Cache ID: 99:E11:101 Discussion No comments yet. Languages: en. Please log in to comment. ◂ PreviousOverviewNext ▸