CVE-2025-65637
Logrus is vulnerable to DoS when using Entry.writerScanner in github.com/sirupsen/logrus
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.
How to fix CVE-2025-65637
To remediate CVE-2025-65637, upgrade the affected package to a fixed version below.
- —no fix listed
- —upgrade to 1.8.3 or later
- —upgrade to 1.8.3 or later
Is CVE-2025-65637 being exploited?
Low — EPSS is 0.1%, meaning exploitation activity has not been observed at scale.
Affected packages (3)
- from 0
- from 0, < 1.8.3
- from 0, < 1.8.3, >= 1.9.0, < 1.9.1, >= 1.9.2, < 1.9.3
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 4.0 | — | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N |
| osv | CVSS 3.1 | HIGH7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |