CVE-2026-104721
Path-traversal vulnerability in QOS.CH Sarl Logback-classic on Java (logback-classic module) allows…
- Risk score
- 43/100
- CVSS
- 6.3 v4.0
- Exploit chance (30 days)
- 0.3%
- Published
- 2 Oct 2026
Open in the live forecast Today's forecast
What to know
- What it is
- Path-traversal vulnerability in QOS.CH Sarl Logback-classic on Java (logback-classic module) allows path-traversal vulnerability. More specifically, an MDC-based discriminator value flows unsanitized into a nested FileAppender path, letting an attacker who influences that MDC value (e.g. via an HTTP header) create and…
- Affected
- See advisory
- Fix
- Apply the vendor's security update; see the linked advisory.
- Exploitation
- No known exploitation
Why it is Yellow
- CVSS 6.3 medium
References
Original description
Path-traversal vulnerability in QOS.CH Sarl Logback-classic on Java (logback-classic module) allows path-traversal vulnerability. More specifically, an MDC-based discriminator value flows unsanitized into a nested FileAppender path, letting an attacker who influences that MDC value (e.g. via an HTTP header) create and append log files outside the intended directory. This issue affects Logback-classic: from 0.9.14 through 1.6.4. This vulnerability is similar to CVE-2026-19880 but involves other attack techniques.
Last activity 2 Oct 2026. Patch Forecast updates every hour.