Quick answers
- Is CVE-2026-44726 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-44726 being exploited in the wild.
- How severe is CVE-2026-44726?
- High severity, with a CVSS score of 7.4, published 27 May 2026.
- Which products and versions are affected?
- deno (crates.io) >= 2.0.0, < 2.7.8, SEMVER:introduced=2.0.0,fixed=2.7.8.
- Is there a fix for CVE-2026-44726?
- Yes. deno (crates.io): upgrade to 2.7.8 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-44726 attacked?
- It is attacked over the network, in a software library.
- Am I affected by CVE-2026-44726?
- Check whether you run deno (crates.io) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
How to fix
- deno (crates.io): upgrade to 2.7.8 or later
cargo update -p deno
Technical details
A vulnerability exists in Deno's Node.js 'tls' compatibility layer (specifically affecting node:tls and node:https) when 'autoSelectFamily' is enabled. When an initial connection attempt fails (e.g., an IPv6 timeout), the socket reinitialization path reuses a stale TLS upgrade hook bound to the original failed handle. Consequently, the fallback TCP connection (e.g., IPv4) is never upgraded to TLS. Any data written by the application before the 'secureConnect' event is transmitted as plaintext. A network-positioned attacker can trigger this by dropping packets to force a connection retry, allowing them to intercept or tamper with traffic. The issue is fixed in Deno version 2.7.8.
Affected products
- denoland Deno >= 2.0.0, < 2.7.8
Identifiers
- CVE-2026-44726
- GHSA-chqv-56wv-7564
Timeline
- 2026-05-27: advisory: GitHub advisory GHSA-chqv-56wv-7564 published
- 2026-06-23: disclosed: CVE-2026-44726 published to NVD
- 2026-06-23: patched: Vulnerability fixed in version 2.7.8