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TI-2024-33236 Aliases CVE-2024-49769GHSA-3f84-rpwh-47g6

Waitress has a denial of service leading to high CPU usage/resource exhaustion

Priority MEDIUM 42CWE-772Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Partial Red Hat: 8 fixed, 3 without a fix

Attack profile from CVSS 3.1 · CNA. Fix status from CNA, GitHub and Red Hat. Impact type from CWE-772.

Summary

Waitress is a Web Server Gateway Interface server for Python 2 and 3. When a remote client closes the connection before waitress has had the opportunity to call getpeername() waitress won't correctly clean up the connection leading to the main thread attempting to write to a socket that no longer exists, but not removing it from the list of sockets to attempt to process. This leads to a busy-loop calling the write function. A remote attacker could run waitress out of available sockets with very little resources required. Waitress 3.0.1 contains fixes that remove the race condition.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.01377 72nd percentileScored 2026-11-07
Fix Partial waitress (Pylons): 3.0.1waitress (PyPI): 3.0.1Red Hat: 9 advisoriesRed Hat: 8 fixed, 3 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
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
Pylonswaitressbefore 3.0.13.0.1Patch availableCNA
—waitress (PyPI)before 3.0.13.0.1Patch availableGHSA-3f84-rpwh-47g6
  • waitress VendorPylons Affected before 3.0.1 Fixed in 3.0.1 Patch available CNA
  • waitress (PyPI) Vendor— Affected before 3.0.1 Fixed in 3.0.1 Patch available GHSA-3f84-rpwh-47g6

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:agendaless:waitress:*:*:*:*:*:*:*:*before 3.0.1VulnerableAgendaless
  • cpe:2.3:a:agendaless:waitress:*:*:*:*:*:*:*:* Versions before 3.0.1 Vulnerable ·Agendaless

Remediation

  • Fix · CNA waitress (Pylons) Fixed in 3.0.1
  • Fix · GHSA-3f84-rpwh-47g6 waitress (PyPI) Fixed in 3.0.1 Advisory →

Red Hat 9 advisories

  • RHSA-2025:1192 Released 2025-02-10 · Red Hat rating Important
    Red Hat OpenStack Platform 17.1 (python-waitress) security update
    • Red Hat OpenStack Platform 17.1 python-waitress-2.0.0-4.el8ost, python3-waitress-2.0.0-4.el8ost
  • RHSA-2025:1191 Released 2025-02-10 · Red Hat rating Important
    Red Hat OpenStack Platform 17.1 (python-waitress) security update
    • Red Hat OpenStack Platform 17.1 python-waitress-2.0.0-4.el9ost, python3-waitress-2.0.0-4.el9ost
  • RHSA-2025:0201 Released 2025-01-09 · Red Hat rating Important
    Red Hat OpenStack Platform 16.2 (python-waitress) security update
    • Red Hat OpenStack Platform 16.2 python-waitress-2.0.0-4.el8ost, python3-waitress-2.0.0-4.el8ost
Show 6 more Red Hat advisories
  • RHSA-2024:10815 Released 2024-12-12 · Red Hat rating Important
    OpenShift Container Platform 4.13.54 packages and security update
    • Ironic content for Red Hat OpenShift Container Platform 4.13 python-waitress-3.0.1-1.el9, python3-waitress-3.0.1-1.el9
  • RHSA-2024:10535 Released 2024-12-05 · Red Hat rating Important
    OpenShift Container Platform 4.12.70 security update
    • Ironic content for Red Hat OpenShift Container Platform 4.12 python-waitress-3.0.1-1.el9, python3-waitress-3.0.1-1.el9
  • RHSA-2024:10145 Released 2024-11-26 · Red Hat rating Important
    OpenShift Container Platform 4.15.39 packages and security update
    • Ironic content for Red Hat OpenShift Container Platform 4.15 python-waitress-3.0.1-1.el9, python3-waitress-3.0.1-1.el9
  • RHSA-2024:9623 Released 2024-11-20 · Red Hat rating Important
    OpenShift Container Platform 4.14.41 packages and security update
    • Ironic content for Red Hat OpenShift Container Platform 4.14 python-waitress-3.0.1-1.el9, python3-waitress-3.0.1-1.el9
  • RHSA-2024:9618 Released 2024-11-20 · Red Hat rating Important
    OpenShift Container Platform 4.16.23 packages and security update
    • Ironic content for Red Hat OpenShift Container Platform 4.16 python-waitress-3.0.1-1.el9, python3-waitress-3.0.1-1.el9
  • RHSA-2024:9613 Released 2024-11-19 · Red Hat rating Important
    OpenShift Container Platform 4.17.5 security update
    • Ironic content for Red Hat OpenShift Container Platform 4.17 python-waitress-3.0.1-1.el9, python3-waitress-3.0.1-1.el9

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat Ceph Storage 4AffectedNo fix planned: Out of support scope
Red Hat Ceph Storage 5AffectedNo fix planned: Out of support scope
Red Hat Openshift Container Storage 4AffectedNo fix yet
Ironic content for Red Hat OpenShift Container Platform 4.12Fixed RHSA-2024:10535
Ironic content for Red Hat OpenShift Container Platform 4.13Fixed RHSA-2024:10815
Ironic content for Red Hat OpenShift Container Platform 4.14Fixed RHSA-2024:9623
Ironic content for Red Hat OpenShift Container Platform 4.15Fixed RHSA-2024:10145
Ironic content for Red Hat OpenShift Container Platform 4.16Fixed RHSA-2024:9618
Ironic content for Red Hat OpenShift Container Platform 4.17Fixed RHSA-2024:9613
Red Hat OpenStack Platform 16.2Fixed RHSA-2025:0201
Red Hat OpenStack Platform 17.1Fixed RHSA-2025:1191, RHSA-2025:1192
Not affected: 5 products
  • Red Hat OpenShift Container Platform 4.12
  • Red Hat OpenShift Container Platform 4.13
  • Red Hat OpenShift Container Platform 4.14
  • Red Hat OpenShift Container Platform 4.16
  • Red Hat OpenShift Container Platform 4.17

Timeline

  1. 2026-10-02 Threatist record created from CVE-2024-49769
  2. 2026-10-03 Alias added: GHSA-3f84-rpwh-47g6

References

Patch 2

Advisory 2

Other 4

  • TI-2022-13060 Uncaught Exception (due to a data race) leads to process termination in Waitress CVSS 3.1MEDIUM 6.5
  • TI-2026-39576 WebOb: Open redirect in Location header normalization via leading C0 control / space characters CVSS 3.1MEDIUM 6.1
  • TI-2024-33235 Waitress has request processing race condition in HTTP pipelining with invalid first request CVSS 3.1CRITICAL 9.1
  • TI-2022-08575 HTTP Request Smuggling in waitress CVSS 3.1HIGH 7.5
  • TI-2019-12566 HTTP Request Smuggling in Waitress: Invalid whitespace characters in headers CVSS 3.1HIGH 8.2
  • TI-2019-12564 HTTP Request Smuggling: LF vs CRLF handling in Waitress CVSS 3.1HIGH 7.5
See all 14 →

Sources

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