CVE-2026-44726
Deno's TLS retry copies stale upgrade hook, risking plaintext traffic
Severity by source
Trivy's own label is CRITICAL. Rated critical by NVD, Julia. Rated lower by GHSA (high).
Description
Deno is a JavaScript, TypeScript, and WebAssembly runtime. From 2.0.0 until 2.7.8, a flaw in Deno's Node.js tls compatibility layer could cause a TLS client to transmit application data in plaintext after a connection retry. When `autoSelectFamily was enabled and the first address-family attempt failed, the socket reinitialization path reused a stale TLS upgrade hook that was bound to the original, failed handle. As a result, the replacement TCP connection was never upgraded to TLS, and any data the application wrote before the secureConnect event travelled over the network unencrypted. A network attacker positioned to cause the initial connection attempt to fail (for example, by dropping IPv6 traffic on a dual-stack host) could deterministically trigger the fallback path and observe or tamper with traffic that the application believed was TLS-protected. This vulnerability is fixed in 2.7.8.
Affected packages and fixed versions
| Source | Package | Fixed in |
|---|---|---|
| julia::Julia Ecosystem Security Advisories | Deno_jll | 2.8.1+0 |
| cargo::GitHub Security Advisory Rust | deno | 2.7.8 |
| rapidfort alpine 3.20 | deno | no fix listed |
| rapidfort alpine 3.21 | deno | no fix listed |
| rapidfort alpine 3.22 | deno | no fix listed |
| rapidfort alpine 3.23 | deno | no fix listed |
| rapidfort alpine 3.24 | deno | no fix listed |