Apache Tika is vulnerable to entity expansions which can lead to a denial of service attack

Exploitation

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

CVSS

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

EPSS

• CVE-2018-11796: 7.54% estimated exploitation activity in the next 30 days; percentile 94.52 (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.

In Apache Tika 1.19 (CVE-2018-11761), we added an entity expansion limit for XML parsing. However, Tika reuses SAXParsers and calls reset() after each parse, which, for Xerces2 parsers, as per the documentation, removes the user-specified SecurityManager and thus removes entity expansion limits after the first parse. Apache Tika versions from 0.1 to 1.19 are therefore still vulnerable to entity expansions which can lead to a denial of service attack. Users should upgrade to 1.19.1 or later.

Published by the source

17 Oct 2018, 15:43 UTC

Last modified by the source

9 Jan 2023, 05:03 UTC

Source last checked

26 Oct 2026, 15:52 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-h8q5-g2cj-qr5h

Preview the exact text before you copy it. Commands are read-only suggestions; review them before running anything.

# Patch Next advisory brief: CVE-2018-11796

Advisory: Apache Tika is vulnerable to entity expansions which can lead to a denial of service attack
IDs: CVE-2018-11796, GHSA-h8q5-g2cj-qr5h
Record: https://patchnext.com/advisories/cve-2018-11796 (revision 1, source checked 26 Oct 2026, 15:52 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 7.5)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: org.apache.tika:tika-core 1.19.1. A vendor fix does not mean a deployment is fixed.

## Affected components
- Maven org.apache.tika:tika-core: affected >= 0.1, < 1.19.1; fixed in 1.19.1

## Suggested inspection (read-only)
- Maven org.apache.tika:tika-core: 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 org.apache.tika:tika-core.
- 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-h8q5-g2cj-qr5h (GitHub-reviewed advisory GHSA-h8q5-g2cj-qr5h lists affected ranges: Maven org.apache.tika:tika-core >=0.1 <1.19.1)

Commands are suggestions: review each one before running it.