QOS.ch Logback vulnerable to Deserialization of Untrusted Data

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

9.8 · CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS

• CVE-2017-5929: 7.50% estimated exploitation activity in the next 30 days; percentile 94.49 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

QOS.ch Logback before 1.2.0 has a serialization vulnerability affecting the SocketServer and ServerSocketReceiver components. The RemoteStreamAppenderClient class in logback-classic and the SocketNode classes in logback-classic and logback-access allow data to be deserialized over a Java Socket, via an ObjectInputStream, without validating the data beforehand. When data is received from the Socket, to be logged, it is deserialized into Java objects.An attacker can exploit this vulnerability by sending malicious, serialized Java objects over the connection to the Socket, which may result in execution of arbitrary code when those objects are deserialized. Note that although logback-core is implicated by the Logback project here, the Sonatype Security Research team discovered that the vulnerability is actually present in the logback-classic and logback-access components. Versions prior to 1.2.0 are vulnerable, as stated in the advisory.

Published by the source

7 Jun 2021, 16:07 UTC

Last modified by the source

28 Jan 2023, 05:00 UTC

Source last checked

26 Oct 2026, 16:01 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-vmfg-rjjm-rjrj

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# Patch Next advisory brief: CVE-2017-5929

Advisory: QOS.ch Logback vulnerable to Deserialization of Untrusted Data
IDs: CVE-2017-5929, GHSA-vmfg-rjjm-rjrj
Record: https://patchnext.com/advisories/cve-2017-5929 (revision 1, source checked 26 Oct 2026, 16:01 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Critical (CVSS 9.8)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: ch.qos.logback:logback-core 1.2.0; ch.qos.logback:logback-classic 1.2.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- Maven ch.qos.logback:logback-core: affected < 1.2.0; fixed in 1.2.0
- Maven ch.qos.logback:logback-classic: affected < 1.2.0; fixed in 1.2.0

## Suggested inspection (read-only)
- Maven ch.qos.logback:logback-core: check the installed version with your package manager.
- Maven ch.qos.logback:logback-classic: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on ch.qos.logback:logback-core, ch.qos.logback:logback-classic.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-vmfg-rjjm-rjrj (GitHub-reviewed advisory GHSA-vmfg-rjjm-rjrj lists affected ranges: Maven ch.qos.logback:logback-classic >=0 =0 <1.2.0)

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