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Fencer Vulns
high 7.5

CVE-2024-52804 json

Tornado has HTTP cookie parsing DoS vulnerability

published 2024-11-22 23 mo ago modified 2026-09-10 1 mo ago also EUVD-2024-3349 , GHSA-8w49-h785-mj3c , PYSEC-2026-1975

cvss
7.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
1.0%
EPSS 1.0% chance of exploitation in 30 days, percentile 64%
public exploits
0
none known

Summary

Tornado is a Python web framework and asynchronous networking library. The algorithm used for parsing HTTP cookies in Tornado versions prior to 6.4.2 sometimes has quadratic complexity, leading to excessive CPU consumption when parsing maliciously-crafted cookie headers. This parsing occurs in the event loop thread and may block the processing of other requests. Version 6.4.2 fixes the issue.

Patch / fix

  • pypi tornado 6.4.2
  • tornadoweb tornado 6.4.2
  • python-tornado Debian 12 6.2.0-3+deb12u1
  • python-tornado Debian 14, Debian 13 6.4.2-1

debian advisories DEBIAN-CVE-2024-52804

  • python-tornado Ubuntu 24.04 LTS 6.4.0-1ubuntu0.1
  • python-tornado Ubuntu 25.10 6.4.2-1
  • python-tornado Ubuntu Pro 18.04 LTS 4.5.3-1ubuntu0.2+esm1
  • python-tornado Ubuntu Pro 20.04 LTS 6.0.3+really5.1.1-3ubuntu0.1~esm1
  • python-tornado Ubuntu Pro 22.04 LTS 6.1.0-3ubuntu0.1~esm1

ubuntu advisories UBUNTU-CVE-2024-52804

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • pcs RHEL 8 0.10.18-2.el8_10.4
  • pcs-snmp RHEL 8 0.10.18-2.el8_10.4
  • pcs RHEL 9 0.11.8-1.el9_5.2
  • pcs-snmp RHEL 9 0.11.8-1.el9_5.2
  • python-tornado RHEL 9 6.4.2-1.el9_5
  • python3-tornado RHEL 9 6.4.2-1.el9_5
  • pcs RHEL 9.2 EUS 0.11.4-7.el9_2.4
  • pcs-snmp RHEL 9.2 EUS 0.11.4-7.el9_2.4

red hat advisories RHSA-2025:3108RHSA-2025:3109RHSA-2025:2956RHSA-2025:2955RHSA-2025:2872RHSA-2025:2550

  • python-tornado6 Linux Micro 6.1 6.4-slfo.1.1_2.1
  • python-tornado6 Linux Micro 6.0 6.4-2.1
  • python-tornado6 SLE Module for Python 3 15 SP6, SLE Module for Python 3 15 SP5, openSUSE Leap 15.6 +1 more 6.3.2-150400.9.6.1

suse advisories SUSE-SU-2025:20445-1SUSE-SU-2025:20096-1SUSE-SU-2024:4137-1

  • python-tornado6 openSUSE Tumbleweed 6.4.2-1.1

opensuse advisories openSUSE-SU-2024:14528-1

  • pcs AlmaLinux 8 0.10.18-2.el8_10.4.alma.1
  • pcs-snmp AlmaLinux 8 0.10.18-2.el8_10.4.alma.1
  • python3-tornado AlmaLinux 9 6.4.2-1.el9_5

almalinux advisories ALSA-2025:2872ALSA-2024:10590

  • pcs Rocky Linux 9 0.11.8-1.el9_5.2
  • pcs Rocky Linux 8 0.10.18-2.el8_10.4
  • python-tornado Rocky Linux 9 6.4.2-1.el9_5

rocky linux advisories RLSA-2025:2471RLSA-2025:2872RLSA-2024:10590

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-2024-52804 updated cvss 7.5

python-tornado: Tornado has HTTP cookie parsing DoS vulnerability

  • Red Hat Enterprise Linux 7 python-tornado
    affected: workaround, no fix planned “Out of support scope”
  • Red Hat Enterprise Linux AppStream (v. 9) python-tornado 6.4.2-1.el9_5, python3-tornado 6.4.2-1.el9_5
    fixed: vendor fix RHSA-2024:10590
  • Red Hat Enterprise Linux AppStream EUS (v.9.2) python-tornado 6.4.2-1.el9_2, python3-tornado 6.4.2-1.el9_2
    fixed: vendor fix RHSA-2024:10836
  • Red Hat Enterprise Linux AppStream EUS (v.9.4) python-tornado 6.4.2-1.el9_4, python3-tornado 6.4.2-1.el9_4
    fixed: vendor fix RHSA-2024:10843
  • Red Hat Enterprise Linux High Availability (v. 9) pcs 0.11.8-1.el9_5.2, pcs-snmp 0.11.8-1.el9_5.2
    fixed: vendor fix RHSA-2025:2471
  • Red Hat Enterprise Linux High Availability AUS (v.8.4) pcs 0.10.8-1.el8_4.6, pcs-snmp 0.10.8-1.el8_4.6
    fixed: vendor fix RHSA-2025:2955
  • Red Hat Enterprise Linux High Availability E4S (v.8.6) pcs 0.10.12-6.el8_6.7, pcs-snmp 0.10.12-6.el8_6.7
    fixed: vendor fix RHSA-2025:2956
  • Red Hat Enterprise Linux High Availability E4S (v.9.0) pcs 0.11.1-10.el9_0.7, pcs-snmp 0.11.1-10.el9_0.7
    fixed: vendor fix RHSA-2025:2550
show 13 more
  • Red Hat Enterprise Linux High Availability EUS (v.8.8) pcs 0.10.15-4.el8_8.4, pcs-snmp 0.10.15-4.el8_8.4
    fixed: vendor fix RHSA-2025:3109
  • Red Hat Enterprise Linux High Availability EUS (v.9.2) pcs 0.11.4-7.el9_2.4, pcs-snmp 0.11.4-7.el9_2.4
    fixed: vendor fix RHSA-2025:3108
  • Red Hat Enterprise Linux High Availability EUS (v.9.4) pcs 0.11.7-2.el9_4.3, pcs-snmp 0.11.7-2.el9_4.3
    fixed: vendor fix RHSA-2025:2470
  • Red Hat Enterprise Linux High Availability TUS (v.8.6) pcs 0.10.12-6.el8_6.7, pcs-snmp 0.10.12-6.el8_6.7
    fixed: vendor fix RHSA-2025:2956
  • Red Hat Enterprise Linux HighAvailability (v. 8) pcs 0.10.18-2.el8_10.4, pcs-snmp 0.10.18-2.el8_10.4
    fixed: vendor fix RHSA-2025:2872
  • Red Hat Enterprise Linux HighAvailability E4S (v.8.4) pcs 0.10.8-1.el8_4.6, pcs-snmp 0.10.8-1.el8_4.6 Red Hat Enterprise Linux HighAvailability TUS (v.8.4) pcs 0.10.8-1.el8_4.6, pcs-snmp 0.10.8-1.el8_4.6
    fixed: vendor fix RHSA-2025:2955
  • Red Hat Enterprise Linux Resilient Storage (v. 9) pcs 0.11.8-1.el9_5.2, pcs-snmp 0.11.8-1.el9_5.2
    fixed: vendor fix RHSA-2025:2471
  • Red Hat Enterprise Linux Resilient Storage EUS (v.8.8) pcs 0.10.15-4.el8_8.4, pcs-snmp 0.10.15-4.el8_8.4
    fixed: vendor fix RHSA-2025:3109
  • Red Hat Enterprise Linux Resilient Storage EUS (v.9.2) pcs 0.11.4-7.el9_2.4, pcs-snmp 0.11.4-7.el9_2.4
    fixed: vendor fix RHSA-2025:3108
  • Red Hat Enterprise Linux Resilient Storage EUS (v.9.4) pcs 0.11.7-2.el9_4.3, pcs-snmp 0.11.7-2.el9_4.3
    fixed: vendor fix RHSA-2025:2470
  • Red Hat Enterprise Linux ResilientStorage (v. 8) pcs 0.10.18-2.el8_10.4, pcs-snmp 0.10.18-2.el8_10.4
    fixed: vendor fix RHSA-2025:2872
  • Red Hat Enterprise Linux ResilientStorage E4S (v.9.0) pcs 0.11.1-10.el9_0.7, pcs-snmp 0.11.1-10.el9_0.7
    fixed: vendor fix RHSA-2025:2550
  • Red Hat Enterprise Linux 10 pcs Red Hat OpenShift Container Platform 4 python-tornado
    not affected: vulnerable code not present

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
none
Automatable
yes
Technical impact
partial
Assessed
23 mo ago

Exploit prediction

1.04% chance of exploitation in the next 30 days, higher than 64% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
GitHub 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
OSV 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected packages

ecosystem package affected fixed in
pypi tornado
<6.4.2
6.4.2

Affected products

  • tornadoweb tornado

Classification

Weakness
  • CWE-400 Uncontrolled Resource Consumption
  • CWE-770 Allocation of Resources Without Limits or Throttling

References

Sources

Fencer Vulns 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.

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