Read the docs
TI-2026-79985 Aliases CVE-2026-115775GHSA-3476-c5c2-fr73

Unauthenticated memory exhaustion in Twisted domish XML parser

Priority HIGH 77CWE-400Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Partial Red Hat: 1 without a fix

Attack profile from CVSS 4.0 · CNA. Fix status from CNA, GitHub and Red Hat. Impact type from CWE-400.

Summary

Twisted, an event-based Python framework for internet applications, is affected before 26.10.0rc1. The domish ExpatElementStream parser keeps an unfinished stanza as an in-memory tree with no byte or element limit (CWE-770). An unauthenticated remote peer can keep a container element open and keep adding child elements over one connection, which exhausts server memory and terminates the process.

Written with Claude Haiku 5.5 from the sources below · 2026-10-29

Description from the CNA

Twisted is an event-based framework for internet applications, supporting Python 3.6+. Prior to 26.10.0rc1, the twisted.words.xish.domish ExpatElementStream parser allows an unauthenticated remote peer to keep a container element open while continuously adding child elements. The parser retains the unfinished stanza as an in-memory tree without a byte or element-count limit, and XMPP pre-authentication stream parsing exposes this behavior before credentials are accepted. A single connection can therefore exhaust server memory and terminate the process. This issue is fixed in version 26.10.0rc1.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00444 38th percentileScored 2026-11-07
Fix Partial twisted (twisted): 26.10.0rc1Twisted (PyPI): 26.10.0rc1Red Hat: 1 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
Yes
Technical impact
Partial

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

Affected products

VendorProductAffected versionsFixed inStatusSource
twistedtwistedbefore 26.10.0rc126.10.0rc1Patch availableCNA
—Twisted (PyPI)before 26.10.0rc126.10.0rc1Patch availableGHSA-3476-c5c2-fr73
  • twisted Vendortwisted Affected before 26.10.0rc1 Fixed in 26.10.0rc1 Patch available CNA
  • Twisted (PyPI) Vendor— Affected before 26.10.0rc1 Fixed in 26.10.0rc1 Patch available GHSA-3476-c5c2-fr73

Remediation

Twisted on PyPI is fixed in version 26.10.0rc1. Red Hat Ansible Automation Platform 2 is affected, and Red Hat's plan for it is none available.

Written with Claude Haiku 5.5 from the sources below · 2026-10-29

  • Fix · CNA twisted (twisted) Fixed in 26.10.0rc1
  • Fix · GHSA-3476-c5c2-fr73 Twisted (PyPI) Fixed in 26.10.0rc1 Advisory →

Vendor assessments

Red Hat

Red Hat rating: Important. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Ansible Automation Platform 2AffectedNo fix yet
Not affected: 2 products
  • Red Hat Ansible Automation Platform 2
  • Red Hat OpenStack Platform 16.2

Timeline

  1. 2026-10-23 Threatist record created from CVE-2026-115775
  2. 2026-10-23 Alias added: GHSA-3476-c5c2-fr73
  3. 2026-10-23 Fix available: PyPI/[email protected] · GHSA-3476-c5c2-fr73
  4. 2026-10-23 CVSS score added · GHSA-3476-c5c2-fr73
  5. 2026-10-23 Weakness changed · GHSA-3476-c5c2-fr73
  6. 2026-10-23 5 new references · GHSA-3476-c5c2-fr73
  7. 2026-10-24 Priority changed: MEDIUM → LOW
  8. 2026-10-24 Affected versions changed · Red Hat
  9. 2026-10-24 CVSS score added · Red Hat
  10. 2026-10-25 EPSS moved to the below the 50th percentile
  11. 2026-10-29 CISA SSVC decision points changed
  12. 2026-10-29 Priority changed: LOW → HIGH
  13. 2026-10-29 Affected versions changed · Red Hat

References

Other 5

  • TI-2026-30612 Twisted: Denial of Service (DoS) in twisted.names via Crafted DNS Compression Pointer Chains CVSS 3.1HIGH 7.5
  • TI-2022-06090 Buffer Overflow in Twisted CVSS 3.1HIGH 7.5
  • TI-2024-27732 twisted.web has disordered HTTP pipeline response CVSS 3.1HIGH 8.3
  • TI-2024-27854 HTML injection in HTTP redirect body CVSS 3.1MEDIUM 6.1
  • TI-2026-79989 HTTP request smuggling in Twisted web via bare CR or LF in headers CVSS 3.1MEDIUM 5.4
  • TI-2022-18723 Twisted vulnerable to NameVirtualHost Host header injection CVSS 3.1MEDIUM 5.4
See all 21 →

Sources

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