CVE-2025-31699
Apache Traffic Server: Origin connection still owed a request body is reused, enabling request smuggling
Description
Apache Traffic Server can return an origin connection to the shared pool while the origin is still waiting on a request body the client declared but never fully sent, including when the client used Expect: 100-continue. The origin then reads a later request on that connection as leftover body data, which lets an attacker smuggle requests past ATS access controls, disrupt other users' requests, or poison the cache. This issue affects Apache Traffic Server: from 8.0.0 through 8.1.11, from 9.0.0 through 9.2.15, from 10.0.0 through 10.1.4, 10.2.0. Users are recommended to upgrade to version 9.2.16, 10.1.5, or 10.2.1, which fix the issue.
INFO
Published Date :
Oct. 21, 2026, 7:16 p.m.
Last Modified :
Oct. 28, 2026, 2:10 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | HIGH | f0158376-9dc2-43b6-827c-5f631a4d8d09 | ||||
| CVSS 3.1 | HIGH | MITRE-CVE | ||||
| CVSS 3.1 | HIGH | [email protected] | ||||
| CVSS 4.0 | CRITICAL | f0158376-9dc2-43b6-827c-5f631a4d8d09 | ||||
| CVSS 4.0 | CRITICAL | [email protected] |
Solution
- Upgrade Apache Traffic Server to version 9.2.16.
- Upgrade Apache Traffic Server to version 10.1.5.
- Upgrade Apache Traffic Server to version 10.2.1.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2025-31699.
| URL | Resource |
|---|---|
| https://lists.apache.org/thread/r95dq29ywcd1f4x30snxlqmb12z4s4kc |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2025-31699 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2025-31699
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2025-31699 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2025-31699 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Translated by [email protected]
Oct. 28, 2026
Action Type Old Value New Value Added Translation Title: Apache Traffic Server de Apache Software Foundation, Description: Apache Traffic Server puede devolver una conexión de origen al pool compartido mientras el origen aún está esperando el cuerpo de la solicitud que el cliente declaró pero nunca envió completamente, incluso cuando el cliente utilizó Expect: 100-continue. El origen entonces lee una solicitud posterior en esa conexión como datos residuales del cuerpo, lo que permite a un atacante introducir solicitudes por delante de los controles de acceso de ATS, interrumpir las solicitudes de otros usuarios o envenenar la caché.\n\nEste problema afecta a Apache Traffic Server: desde la versión 8.0.0 hasta la versión 8.1.11 incluida, desde la versión 9.0.0 hasta la versión 9.2.15 incluida, desde la versión 10.0.0 hasta la versión 10.1.4 incluida y la versión 10.2.0.\n\nSe recomienda a los usuarios actualizar a la versión 9.2.16, 10.1.5 o 10.2.1, que corrigen el problema. -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Oct. 23, 2026
Action Type Old Value New Value Removed SSVC {'id': 'CVE-2025-31699', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-10-21T00:00:00+00:00'} Added SSVC {'id': 'CVE-2025-31699', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-10-22T23:05:01.570814Z'} -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Oct. 22, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2025-31699', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-10-21T00:00:00+00:00'} -
New CVE Received by [email protected]
Oct. 21, 2026
Action Type Old Value New Value Added Description Apache Traffic Server can return an origin connection to the shared pool while the origin is still waiting on a request body the client declared but never fully sent, including when the client used Expect: 100-continue. The origin then reads a later request on that connection as leftover body data, which lets an attacker smuggle requests past ATS access controls, disrupt other users' requests, or poison the cache. This issue affects Apache Traffic Server: from 8.0.0 through 8.1.11, from 9.0.0 through 9.2.15, from 10.0.0 through 10.1.4, 10.2.0. Users are recommended to upgrade to version 9.2.16, 10.1.5, or 10.2.1, which fix the issue. Added CVSS V4.0 AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:H/VA:L/SC:H/SI:H/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CVSS V3.1 AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:L Added CWE CWE-444 Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2025/31xxx/CVE-2025-31699.json">CVE-2025-31699</a> Added Reference https://lists.apache.org/thread/r95dq29ywcd1f4x30snxlqmb12z4s4kc