Medium

DEBIAN-CVE-2026-104721

Type: advisorySource: OSV1 source record

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.

Announced 2 Oct 2026Group revision 1

Original source ↗

DEBIAN-CVE-2026-104721

Primary source · Revision 1

Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.

Security context

Source reference: osv:DEBIAN-CVE-2026-104721

logback

Source reference: /affected/0/package/name

Affected versions: 1:1.2.11-3
Source reference: /affected/0/versions
1:1.2.11-4
Source reference: /affected/0/versions
1:1.2.11-5
Source reference: /affected/0/versions
1:1.2.11-6
Source reference: /affected/0/versions
1:1.6.3-1
Source reference: /affected/0/versions
1:1.6.3-2
Source reference: /affected/0/versions
Fixed versions: Not stated in this record
Prerequisites: Not stated in this record

logback

Source reference: /affected/1/package/name

Affected versions: 1:1.2.11-6
Source reference: /affected/1/versions
1:1.6.3-1
Source reference: /affected/1/versions
1:1.6.3-2
Source reference: /affected/1/versions
Fixed versions: Not stated in this record
Prerequisites: Not stated in this record

logback

Source reference: /affected/2/package/name

Affected versions: 1:1.2.11-6
Source reference: /affected/2/versions
1:1.6.3-1
Source reference: /affected/2/versions
1:1.6.3-2
Source reference: /affected/2/versions
Fixed versions: Not stated in this record
Prerequisites: Not stated in this record

Structured affected-version data

Original package identities and version rules from this source.

[
  {
    "ranges": [
      {
        "type": "ECOSYSTEM",
        "events": [
          {
            "introduced": "0"
          }
        ]
      }
    ],
    "package": {
      "name": "logback",
      "purl": "pkg:deb/debian/logback?arch=source&distro=bookworm",
      "ecosystem": "Debian:12"
    },
    "versions": [
      "1:1.2.11-3",
      "1:1.2.11-4",
      "1:1.2.11-5",
      "1:1.2.11-6",
      "1:1.6.3-1",
      "1:1.6.3-2"
    ],
    "database_specific": {
      "source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-104721.json"
    },
    "ecosystem_specific": {
      "urgency": "not yet assigned"
    }
  },
  {
    "ranges": [
      {
        "type": "ECOSYSTEM",
        "events": [
          {
            "introduced": "0"
          }
        ]
      }
    ],
    "package": {
      "name": "logback",
      "purl": "pkg:deb/debian/logback?arch=source&distro=trixie",
      "ecosystem": "Debian:13"
    },
    "versions": [
      "1:1.2.11-6",
      "1:1.6.3-1",
      "1:1.6.3-2"
    ],
    "database_specific": {
      "source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-104721.json"
    },
    "ecosystem_specific": {
      "urgency": "not yet assigned"
    }
  },
  {
    "ranges": [
      {
        "type": "ECOSYSTEM",
        "events": [
          {
            "introduced": "0"
          }
        ]
      }
    ],
    "package": {
      "name": "logback",
      "purl": "pkg:deb/debian/logback?arch=source&distro=forky",
      "ecosystem": "Debian:14"
    },
    "versions": [
      "1:1.2.11-6",
      "1:1.6.3-1",
      "1:1.6.3-2"
    ],
    "database_specific": {
      "source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-104721.json"
    },
    "ecosystem_specific": {
      "urgency": "not yet assigned"
    }
  }
]

Related CVEs: CVE-2026-104721
Source reference: /upstream

Publisher severity

medium

Source reference: /severity/0/score

Linked CVE context

These ratings describe the referenced vulnerabilities and products. They are not a severity rating for every application using this dependency.

CVE-2026-104721 · Medium

Logback-classic

Event: #75224 · Revision 1
Added to Heist Feed: Mon, 26 Oct 2026 03:38:29 GMT
Publisher date: Fri, 02 Oct 2026 14:17:10 GMT

Read the original announcement

Revision history

26 Oct 2026DEBIAN-CVE-2026-104721 · Revision 1Source updated