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Fencer Intel
low 3.1

CVE-2026-83813 json

Twisted: DNS Response Spoofing in twisted.names Due to Missing Source Address Validation

published 20d ago modified 13d ago also EUVD-2026-109152 , GHSA-jj36-9pvh-vj5r

cvss
3.1
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.1%
EPSS 0.1% chance of exploitation in 30 days, percentile 1%
public exploits
0
none known

Summary

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.

Patch / fix

  • pypi twisted 26.10.0rc1
  • twistedmatrix twisted 26.7.0rc1
  • twisted Debian 14 26.10.0-1

debian advisories DEBIAN-CVE-2026-83813

  • python-Twisted openSUSE Tumbleweed 26.10.0-1.1

opensuse advisories openSUSE-SU-2026:12381-1

Is CVE-2026-83813 in your dependencies? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

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Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-83813 updated cvss 3.7

twisted: twisted: DNS spoofing via missing response source verification

  • Red Hat Ansible Automation Platform 2 python-twisted 23.10.0-1.el9ap, python3x-twisted 23.10.0-1.el8ap, python3.11-twisted 24.7.0-1.el9ap, python3.12-twisted 24.7.0-2.el9ap, automation-controller 4.7.18-1.el9ap, ansible-automation-platform-24/controller-rhel8, +8 more
    affected: no fix available, no fix planned “Out of support scope”
  • Red Hat Enterprise Linux 6 python-twisted 23.10.0-1.el9ap Red Hat OpenStack Platform 13 (Queens) python-twisted 23.10.0-1.el9ap
    affected: no fix available “Fix deferred”
  • Red Hat OpenStack Platform 16.2 python3-twisted, python-twisted 23.10.0-1.el9ap
    affected: no fix planned “Out of support scope”

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
Proof of concept is public
Automatable
no
Technical impact
partial
Assessed
13d ago

Exploit prediction

0.11% chance of exploitation in the next 30 days, higher than 1% of all scored CVEs (FIRST EPSS, 2026-11-11).

Exploits and checks

  • github.com https://github.com/twisted/twisted/security/advisories/GHSA-jj36-9pvh-vj5r referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 3.1 3.1 CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N
GitHub 3.1 3.1 CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N

Affected packages

ecosystem package affected fixed in
pypi twisted
<26.10.0rc1
26.10.0rc1

Affected products

  • twisted twisted

Classification

Weakness

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

The maintainers of twisted/twisted published their own advisory on GitHub. Reviewed sources take precedence over it.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.