CVE-2025-65637
Publication date 4 December 2025
Last updated 10 December 2025
Ubuntu priority
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.
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| golang-logrus | 25.10 questing |
Needs evaluation
|
| 24.04 LTS noble |
Needs evaluation
|
|
| 22.04 LTS jammy |
Needs evaluation
|
|
| 20.04 LTS focal |
Needs evaluation
|
|
| 18.04 LTS bionic |
Needs evaluation
|
|
| 16.04 LTS xenial |
Needs evaluation
|
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score |
7.5 · High
|
| Attack vector | Network |
| Attack complexity | Low |
| Privileges required | None |
| User interaction | None |
| Scope | Unchanged |
| Confidentiality | None |
| Integrity impact | None |
| Availability impact | High |
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
References
Other references
- https://www.cve.org/CVERecord?id=CVE-2025-65637
- https://github.com/mjuanxd/logrus-dos-poc
- https://github.com/sirupsen/logrus/issues/1370
- https://github.com/sirupsen/logrus/pull/1384
- https://github.com/sirupsen/logrus/pull/1376
- https://github.com/mjuanxd/logrus-dos-poc/blob/main/README.md
- https://github.com/sirupsen/logrus/releases/tag/v1.8.3
- https://github.com/sirupsen/logrus/releases/tag/v1.9.1
- https://github.com/sirupsen/logrus/releases/tag/v1.9.3
- https://security.snyk.io/vuln/SNYK-GOLANG-GITHUBCOMSIRUPSENLOGRUS-5564391