# CVE-2026-83813: Twisted: DNS Response Spoofing in twisted.names Due to Missing Source Address Validation

Source: https://junglewise.ai/threats/cve-2026-83813-twisted-is-an-event-based-framework-for-internet-applications  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-10-23  
License: CC BY 4.0 with a link back

CVE-2026-83813 · Severity: low · CVSS 3.1 · Published 2026-10-23

Twisted is an event-based framework for internet applications, supporting Python 3.6+. Prior to 26.10.0rc1, twisted.names.dns.DNSDatagramProtocol accepts a UDP DNS response for a pending query when its 16-bit transaction ID matches but does not verify that the response came from the queried host and port. An attacker able to deliver a packet to the resolver's listening port with the correct transaction ID can inject a forged answer. The standard twisted.names.client.Resolver uses a new random source port for each query, increasing off-path attack complexity, while applications that reuse a DNSDatagramProtocol instance expose only the transaction-ID search space after the first query. A successful forgery can redirect hostname resolution and enable mail interception, server-side request forgery, or man-in-the-middle positioning. This issue is fixed in version 26.10.0rc1.

Technologies: [twisted (PyPI)](https://junglewise.ai/threats/technologies/pypi-twisted). Vendors: [PyPI](https://junglewise.ai/threats/vendors/pypi).

## Quick answers

**Is CVE-2026-83813 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-83813 being exploited in the wild.

**How severe is CVE-2026-83813?** Low severity, with a CVSS score of 3.1, published 23 October 2026.

**Which products and versions are affected?** twisted (PyPI) <= 26.4.0, ECOSYSTEM:introduced=0,fixed=26.10.0rc1.

**Is there a fix for CVE-2026-83813?** Yes. twisted (PyPI): upgrade to 26.10.0rc1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**Am I affected by CVE-2026-83813?** Check whether you run twisted (PyPI) 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

- twisted (PyPI): upgrade to 26.10.0rc1 or later

  ```sh
  pip install "twisted>=26.10.0rc1"
  ```


## Affected products

- twisted (PyPI) <= 26.4.0, ECOSYSTEM:introduced=0,fixed=26.10.0rc1

## Identifiers

- CVE-2026-83813
- GHSA-jj36-9pvh-vj5r

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