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