Exploitation ongoing with high activity in latest observed window (2 mentions)
Recommended action window: Immediate (within 24h)
NVD description
nghttp2's nghttpx proxy through 1.69.0 forwards an HTTP/1.1 Upgrade request that also carries a Content-Length header and body onto reusable keep-alive backend connections, re-adding the Upgrade and Connection headers while passing Content-Length verbatim. A backend that resolves the resulting ambiguous message in the attacker's favor enables HTTP request/response smuggling and cross-client response-queue poisoning.
Priority
LOW
Exploitation
ACTIVE
PoC
NONE
Patch
AVAILABLE
Momentum
NONE
If you run products in this scope, you should treat this CVE as relevant to your environment.
Some increased actor activities are shown targeting nghttp2 (CVE-2026-58055) https://vuldb.com/vuln/374509/cti
Post summary
The post indicates that malicious actors are actively exploiting CVE-2026-58055 in nghttp2, with no additional MitM or patch details provided.
CVE-2026-58055 HTTP Request Smuggling in nghttp2 nghttpx Proxy Through Version 1.69.0 https://vulmon.com/vulnerabilitydetails?qid=CVE-2026-58055
Post summary
The post announces CVE-2026-58055 as an HTTP Request Smuggling vulnerability affecting nghttp2 nghttpx Proxy up to version 1.69.0, but does not provide PoC, exploit, or patch information.
1 of 1 entries
| Part | Vendor | Product | Version | Target SW | Target HW |
|---|---|---|---|---|---|
| App | nghttp2 | nghttp2 | - | - | - |