Apache Flex BlazeDS unsafe deserialization

Exploitation

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

CVSS

9.8 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS

• CVE-2017-5641: 20.75% estimated exploitation activity in the next 30 days; percentile 97.54 (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.

Previous versions of Apache Flex BlazeDS (4.7.2 and earlier) did not restrict which types were allowed for AMF(X) object deserialization by default. During the deserialization process code is executed that for several known types has undesired side-effects. Other, unknown types may also exhibit such behaviors. One vector in the Java standard library exists that allows an attacker to trigger possibly further exploitable Java deserialization of untrusted data. Other known vectors in third party libraries can be used to trigger remote code execution.

Published by the source

13 May 2022, 01:02 UTC

Last modified by the source

6 Oct 2023, 21:11 UTC

Source last checked

26 Oct 2026, 16:14 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-w8v7-prhw-xjpw

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# Patch Next advisory brief: CVE-2017-5641

Advisory: Apache Flex BlazeDS unsafe deserialization
IDs: CVE-2017-5641, GHSA-w8v7-prhw-xjpw
Record: https://patchnext.com/advisories/cve-2017-5641 (revision 1, source checked 26 Oct 2026, 16:14 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: org.apache.flex.blazeds:flex-messaging-remoting 4.7.3; org.apache.flex.blazeds:flex-messaging-core 4.7.3. A vendor fix does not mean a deployment is fixed.

## Affected components
- Maven org.apache.flex.blazeds:flex-messaging-remoting: affected <= 4.7.2; fixed in 4.7.3
- Maven org.apache.flex.blazeds:flex-messaging-core: affected <= 4.7.2; fixed in 4.7.3

## Suggested inspection (read-only)
- Maven org.apache.flex.blazeds:flex-messaging-remoting: check the installed version with your package manager.
- Maven org.apache.flex.blazeds:flex-messaging-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.flex.blazeds:flex-messaging-remoting, org.apache.flex.blazeds:flex-messaging-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-w8v7-prhw-xjpw (GitHub-reviewed advisory GHSA-w8v7-prhw-xjpw lists affected ranges: Maven org.apache.flex.blazeds:flex-messaging-core >=0 =0 <=4.7.2)

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