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HIGH

CVE-2017-18640

CVSS v3

7.5

HIGH

EPSS Score

26.7 %

exploit probability, as of 2026-10-19

CISA KEV

No

known exploited

Exploitation

—

SSVC status

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Affected and fixed versions

Packages from OSV.dev and products from the vendors' CSAF advisories.

version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.

Packages

  • org.yaml:snakeyamlMavenall versions · fixed in 1.26
  • prometheus-jmx-exporterAlmaLinux:8all versions · fixed in 0.12.0-6.el8

Vendor advisories

  • CVE-2017-18640 Red Hat Product Security5 products fixed · 6 known affected

    snakeyaml: Billion laughs attack via alias feature

    snakeyaml-javadoc as a component of Red Hat Enterprise Linux 7 · snakeyaml.src as a component of Red Hat Enterprise Linux 7 · rh-java-common-snakeyaml-javadoc as a component of Red Hat Software Collections

  • RHSA-2021:3225 Red Hat Product Security1 product fixed

    Red Hat Security Advisory: Red Hat AMQ Streams 1.8.0 release and security update

  • RHSA-2021:3140 Red Hat Product Security1 product fixed

    Red Hat Security Advisory: Red Hat Fuse 7.9.0 release and security update

  • RHSA-2020:4807 Red Hat Product Security2 products fixed

    Red Hat Security Advisory: prometheus-jmx-exporter security update

  • RHSA-2020:2603 Red Hat Product Security1 product fixed

    Red Hat Security Advisory: Red Hat build of Quarkus 1.3.4 security update

Full record on NVD

Description

The Alias feature in SnakeYAML before 1.26 allows entity expansion during a load operation, a related issue to CVE-2003-1564.

Technical details

Published
2019-12-12

Frequently asked questions

What is CVE-2017-18640?

The Alias feature in SnakeYAML before 1.26 allows entity expansion during a load operation, a related issue to CVE-2003-1564.

Is CVE-2017-18640 actively exploited?

Active exploitation of CVE-2017-18640 has not been confirmed. Its EPSS score was 26.7% on 2026-10-19, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2017-18640?

CVE-2017-18640 has a CVSS v3 base score of 7.5 (HIGH severity).

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Related vulnerabilities

Same product first, then the same vendor advisory and the same publication week.

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