CVE-2026-82397
Tornado: Urlencoded body parsing omits max_num_fields, so one request can stall the event loop
02 Description
Tornado: Urlencoded body parsing omits max_num_fields, so one request can stall the event loop
03 Exploitation and scoring
- Exploitation
- Assessed, none found. CISA's assessment recorded neither public exploit code nor evidence of exploitation when it was made.
- SSVC decision
- ExploitationnoneCISA recorded no public exploit code and no evidence of exploitation.
- AutomatableyesAn attacker can reliably automate reconnaissance through exploitation, so this scales.
- Technical ImpactpartialSuccessful exploitation gives limited control of the vulnerable component.
- EPSS probability
- 0.34% probability of exploitation activity in the next 30 days.
- EPSS percentile
- Equal to or higher than the score of 27.8% of scored records. A rank, not a probability.
- NVD base score
- 7.5 (CVSS v3.x), scored by the NVD independently of the CNA.
- NVD CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- NVD analysis status
- Deferred. NVD last modified this record on 2026-09-09.
- Red Hat severity
- Important. Red Hat's rating for its own products, not a CVSS rating.
Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.
04 Metadata
- Published
- 2026-08-31 21:28Z1 MO AGO
- Last updated
- 2026-09-02 17:39Z1 MO AGO
- Reserved
- 2026-08-28
- Assigning CNA
- GitHub_M
- Record state
- PUBLISHED
- Severity
- High (CVSS 7.5)
- CNA CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- Weaknesses
- Data version
- 5.2
- Document digest
- 8dc0a20b9521949dbc025f6f72ee1c63d8e1cfdeb1a6423633f6a3a14a06fc9a
05 Affected products
06 References
- github.comhttps://github.com/tornadoweb/tornado/security/advisories/GHSA-mpf4-983q-p7j4
- github.comhttps://github.com/tornadoweb/tornado/pull/3704
- github.comhttps://github.com/tornadoweb/tornado/commit/8d6363ed7b69d5f0da806efe34d256627a2191de
- github.comhttps://github.com/tornadoweb/tornado/releases/tag/v6.5.8
07 Fixed in
AlmaLinux 8
- pcs Fixed in 0.10.18-2.el8_10.10.alma.1
- pcs-snmp Fixed in 0.10.18-2.el8_10.10.alma.1
Source: AlmaLinux, AlmaLinux OS. Copyright (c) 2023 AlmaLinux OS. Licensed under MIT License. Received through OSV.dev. Reformatted by exploit.cc.
AlmaLinux 9
- python3-tornado Fixed in 6.5.8-0.el9_8.1
Source: AlmaLinux, AlmaLinux OS. Copyright (c) 2023 AlmaLinux OS. Licensed under MIT License. Received through OSV.dev. Reformatted by exploit.cc.
AlmaLinux 10
- python3-tornado Fixed in 6.5.8-0.el10_2.1
Source: AlmaLinux, AlmaLinux OS. Copyright (c) 2023 AlmaLinux OS. Licensed under MIT License. Received through OSV.dev. Reformatted by exploit.cc.
CloudLinux 8
- pcs Fixed in 0.10.18-2.el8_10.10.alma.1
- pcs-snmp Fixed in 0.10.18-2.el8_10.10.alma.1
Derived from AlmaLinux 8. Partial coverage: only packages taken from AlmaLinux 8 are listed.
Source: CloudLinux errata, CloudLinux Inc. Derived from: AlmaLinux, AlmaLinux OS. Copyright (c) 2023 AlmaLinux OS. Licensed under MIT License. Received through OSV.dev. Reformatted by exploit.cc.
CloudLinux 9
- python3-tornado Fixed in 6.5.8-0.el9_8.1
Derived from AlmaLinux 9. Partial coverage: only packages taken from AlmaLinux 9 are listed.
Source: CloudLinux errata, CloudLinux Inc. Derived from: AlmaLinux, AlmaLinux OS. Copyright (c) 2023 AlmaLinux OS. Licensed under MIT License. Received through OSV.dev. Reformatted by exploit.cc.
CloudLinux 10
- python3-tornado Fixed in 6.5.8-0.el10_2.1
Derived from AlmaLinux 10. Partial coverage: only packages taken from AlmaLinux 10 are listed.
Source: CloudLinux errata, CloudLinux Inc. Derived from: AlmaLinux, AlmaLinux OS. Copyright (c) 2023 AlmaLinux OS. Licensed under MIT License. Received through OSV.dev. Reformatted by exploit.cc.
Debian 12
- python-tornado No fix yet
Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.
Debian 13
- python-tornado No fix yet
Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.
Debian 14
- python-tornado No fix yet
Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 24.04 LTS
- python-tornado No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 26.04 LTS
- python-tornado No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 26.10
- python-tornado No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu Pro 16.04 LTS
- python-tornado No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu Pro 18.04 LTS
- python-tornado No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu Pro 20.04 LTS
- python-tornado No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu Pro 22.04 LTS
- python-tornado No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
A release or ecosystem missing from this list has no record here. It may be unaffected or not covered by the source. Source notices and licences.