CVE-2026-83813
An attacker able to deliver a packet to the resolver's listening port with the correct transaction ID can inject a forged answer.
Does this matter?
Lower severity and a low EPSS score (0.11%). Track it; it rarely justifies an emergency change on its own.
Description
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.
- CVSS 3.1
- 3.1 LOWCVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N
- EPSS
- 0.11% probability · 1th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-346
- Source
- security-advisories@github.com
EPSS moved from 0.2% on 24 October 2026 to 0.1% on 26 October 2026.
References
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.