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TI-2026-32613 Aliases CVE-2026-44726GHSA-chqv-56wv-7564

Deno: TLS retry copies stale upgrade hook, risking plaintext traffic

Priority MEDIUM 41CWE-319Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Information disclosure
Confidentiality · integrity · availability
High · High · None
Fix status
Fixed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and GitHub. Impact type from CWE-319.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00234 14th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Fixed deno (denoland): 2.7.8deno (crates.io): 2.7.8

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
denolanddeno2.0.0 to before 2.7.82.7.8Patch availableCNA
—deno (crates.io)2.0.0 to before 2.7.82.7.8Patch availableGHSA-chqv-56wv-7564
  • deno Vendordenoland Affected 2.0.0 to before 2.7.8 Fixed in 2.7.8 Patch available CNA
  • deno (crates.io) Vendor— Affected 2.0.0 to before 2.7.8 Fixed in 2.7.8 Patch available GHSA-chqv-56wv-7564

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:deno:deno:*:*:*:*:*:*:*:*2.0.0 to before 2.7.8Vulnerabledenoland
  • cpe:2.3:a:deno:deno:*:*:*:*:*:*:*:* Versions 2.0.0 to before 2.7.8 Vulnerable ·denoland

Remediation

  • Fix · CNA deno (denoland) Fixed in 2.7.8
  • Fix · GHSA-chqv-56wv-7564 deno (crates.io) Fixed in 2.7.8 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-44726
  2. 2026-10-03 Alias added: GHSA-chqv-56wv-7564

References

Exploit 1

Advisory 1

Other 1

  • TI-2026-21627 Deno has a Command Injection via Incomplete shell metacharacter blocklist in node:child_process CVSS 3.1CRITICAL 9.8
  • TI-2025-17782 Deno's AES GCM authentication tags are not verified CVSS 4.0HIGH 7.7
  • TI-2024-18537 *const c_void / ExternalPointer unsoundness leading to use-after-free CVSS 3.1HIGH 8.8
  • TI-2024-18536 Deno arbitrary file descriptor close via `op_node_ipc_pipe()` leading to permission prompt bypass CVSS 3.1HIGH 8.8
  • TI-2023-12990 Deno is vulnerable to interactive `run` permission prompt spoofing via improper ANSI neutralization CVSS 3.1HIGH 8.8
  • TI-2023-11328 Regular expression denial of service in deno CVSS 3.1HIGH 7.5
See all 37 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences