CVE-2025-65637
Logrus Denial-of-Service Vulnerability
Description
A denial-of-service vulnerability exists in github.com/sirupsen/logrus when using Entry.Writer() to log a single-line payload larger than 64KB without newline characters. Due to limitations in the internal bufio.Scanner, the read fails with "token too long" and the writer pipe is closed, leaving Writer() unusable and causing application unavailability (DoS). This affects versions < 1.8.3, 1.9.0, and 1.9.2. The issue is fixed in 1.8.3, 1.9.1, and 1.9.3+, where the input is chunked and the writer continues to function even if an error is logged.
INFO
Published Date :
Dec. 4, 2025, 7:16 p.m.
Last Modified :
Dec. 23, 2025, 12:26 a.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | HIGH | 134c704f-9b21-4f2e-91b3-4a467353bcc0 |
Solution
- Update the logrus library to version 1.8.3 or later.
- Apply patches to fix the bufio.Scanner input handling.
- Ensure input is chunked to prevent writer pipe closure.
Public PoC/Exploit Available at Github
CVE-2025-65637 has a 1 public
PoC/Exploit available at Github.
Go to the Public Exploits tab to see the list.
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-2025-65637.
| URL | Resource |
|---|---|
| https://github.com/mjuanxd/logrus-dos-poc | Exploit Third Party Advisory |
| https://github.com/mjuanxd/logrus-dos-poc/blob/main/README.md | Exploit Third Party Advisory |
| https://github.com/sirupsen/logrus/issues/1370 | Exploit Issue Tracking Patch |
| https://github.com/sirupsen/logrus/pull/1376 | Issue Tracking Patch |
| https://github.com/sirupsen/logrus/releases/tag/v1.8.3 | Release Notes |
| https://github.com/sirupsen/logrus/releases/tag/v1.9.1 | Release Notes |
| https://github.com/sirupsen/logrus/releases/tag/v1.9.3 | Release Notes |
| https://security.snyk.io/vuln/SNYK-GOLANG-GITHUBCOMSIRUPSENLOGRUS-5564391 | Exploit Third Party Advisory |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2025-65637 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-2025-65637
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).
CVE-2025-65637: Logrus Denial of Service Vulnerability
Go PowerShell Shell
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2025-65637 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2025-65637 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.
-
Initial Analysis by [email protected]
Dec. 23, 2025
Action Type Old Value New Value Added CPE Configuration OR *cpe:2.3:a:turbopuffer:logrus:*:*:*:*:*:go:*:* versions up to (excluding) 1.8.3 *cpe:2.3:a:turbopuffer:logrus:1.9.0:*:*:*:*:go:*:* *cpe:2.3:a:turbopuffer:logrus:1.9.2:*:*:*:*:go:*:* Added Reference Type MITRE: https://github.com/mjuanxd/logrus-dos-poc Types: Exploit, Third Party Advisory Added Reference Type MITRE: https://github.com/mjuanxd/logrus-dos-poc/blob/main/README.md Types: Exploit, Third Party Advisory Added Reference Type MITRE: https://github.com/sirupsen/logrus/issues/1370 Types: Exploit, Issue Tracking, Patch Added Reference Type MITRE: https://github.com/sirupsen/logrus/pull/1376 Types: Issue Tracking, Patch Added Reference Type MITRE: https://github.com/sirupsen/logrus/releases/tag/v1.8.3 Types: Release Notes Added Reference Type MITRE: https://github.com/sirupsen/logrus/releases/tag/v1.9.1 Types: Release Notes Added Reference Type MITRE: https://github.com/sirupsen/logrus/releases/tag/v1.9.3 Types: Release Notes Added Reference Type MITRE: https://security.snyk.io/vuln/SNYK-GOLANG-GITHUBCOMSIRUPSENLOGRUS-5564391 Types: Exploit, Third Party Advisory -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Dec. 05, 2025
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Added CWE CWE-400 -
New CVE Received by [email protected]
Dec. 04, 2025
Action Type Old Value New Value Added Description A denial-of-service vulnerability exists in github.com/sirupsen/logrus when using Entry.Writer() to log a single-line payload larger than 64KB without newline characters. Due to limitations in the internal bufio.Scanner, the read fails with "token too long" and the writer pipe is closed, leaving Writer() unusable and causing application unavailability (DoS). This affects versions < 1.8.3, 1.9.0, and 1.9.2. The issue is fixed in 1.8.3, 1.9.1, and 1.9.3+, where the input is chunked and the writer continues to function even if an error is logged. Added Reference https://github.com/mjuanxd/logrus-dos-poc Added Reference https://github.com/mjuanxd/logrus-dos-poc/blob/main/README.md Added Reference https://github.com/sirupsen/logrus/issues/1370 Added Reference https://github.com/sirupsen/logrus/pull/1376 Added Reference https://github.com/sirupsen/logrus/releases/tag/v1.8.3 Added Reference https://github.com/sirupsen/logrus/releases/tag/v1.9.1 Added Reference https://github.com/sirupsen/logrus/releases/tag/v1.9.3 Added Reference https://security.snyk.io/vuln/SNYK-GOLANG-GITHUBCOMSIRUPSENLOGRUS-5564391