Last updated: September 29, 2026 at 8:42 AM UTC
All 891 Vulnerability 357 Breach 144 Threat 383 Defense 7
Tag: web-server (2 articles)Clear

LiteSpeed Enterprise flaw lets one hosting tenant gain root on a shared server

LiteSpeed disclosed that versions of its Enterprise web server before 6.3.7 contain a flaw that lets a low-privilege website user gain root access on the underlying server. On shared hosting, that means one tenant, reachable through a cheap plan or a stolen webmail login, can take over the whole machine and every other customer on it. Neither LiteSpeed nor cPanel has published how the flaw works, its severity, a CVE identifier, or whether it has been exploited, leaving defenders with little to hunt for. Because the update may be slow to arrive automatically, administrators are urged to install 6.3.7 manually. LiteSpeed's cPanel plugin had two similar exploited flaws earlier this year.

Check
Manually update LiteSpeed Enterprise to 6.3.7 now rather than waiting for auto-update, and on shared servers review tenant activity and privileges for signs of abuse given the missing technical details.
Affected
Shared-hosting providers and multi-tenant servers running LiteSpeed Enterprise before 6.3.7; a low-privilege website user can escalate to root and take over the entire server, exposing every other tenant's sites and data.
Fix
Install 6.3.7 manually across affected servers, isolate tenants, monitor for unexpected root processes and privilege escalation, rotate credentials on any suspected compromise, and treat shared hosting as one account from takeover.

Critical F5 NGINX flaws allow unauthenticated code execution and crashes

F5 has issued out-of-band patches for two critical flaws in NGINX, the web server and reverse proxy that runs a large share of the internet. CVE-2026-42530 (a use-after-free in the HTTP/3 module) and CVE-2026-42055 (a heap overflow in the HTTP/2 proxy and gRPC modules), both rated 9.2, let a remote, unauthenticated attacker corrupt memory in an NGINX worker, crashing it for a denial of service and, where address-space randomization is disabled or bypassed, potentially running code. They affect non-default configurations across NGINX Open Source, Plus, Gateway Fabric, and Instance Manager. F5 has not seen exploitation yet, but its products are frequent attacker targets.

Check
Inventory NGINX instances and versions across servers, ingress, and gateways, and check whether HTTP/3 (QUIC) or HTTP/2 proxy and gRPC upstreams are enabled, which is what exposes these flaws.
Affected
NGINX Open Source, NGINX Plus, Gateway Fabric, and Instance Manager in non-default configurations using HTTP/3 (CVE-2026-42530) or HTTP/2 proxying and gRPC (CVE-2026-42055); unauthenticated remote attackers can trigger the flaws.
Fix
Upgrade to the fixed releases (NGINX Open Source 1.31.2, Plus 37.0.2.1 or R36 P6, Gateway Fabric 2.6.4). If you cannot patch now, disable HTTP/3 or the affected proxy settings as F5 advises.