WaratekVRT Sign in

CVE-2017-18640 SnakeYAML

Affected softwareSnakeYAML
Severity7.5 High CVSS 3.1 2 scores
Fixed in1.26
WeaknessXML entity expansion (CWE-776)
Published12 Dec 2019
Updated17 Jun 2026

Description

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

Exploitation status

No public exploit

No exploit has been reported in the sources we check. Published 6 years ago.

  • CISA KEV not listed
  • VulnCheck KEV not listed
  • CISA Vulnrichment no assessment published
  • Indexed PoC none indexed
  • EPSS 27% chance in 30 days A model's forecast, not a report of exploitation. Higher than 98% of all scored CVEs.

Waratek protection

Protected by Waratek

Waratek has a rule that blocks attacks on this vulnerability.

  • Protection full XXE
  • Action available security rule
  • Review automated Inferred
  • Record active
Decided by A vulnerability class already blocked by an ARMR security rule
Finding Protected by Waratek's ARMR xxe security rule, which blocks this class of attack at the JVM level without a rule written for this CVE specifically. The CVE's weakness is CWE-776: XML Entity Expansion.

How to mitigate CVE-2017-18640

Upgrade SnakeYAML to 1.26 or later. Until you can, Waratek RASP blocks exploitation with its XXE rule. It runs inside the Java application, with no code changes.

Waratek RASP Runtime protection for Java applications

CVSS

7.5 HIGH v3.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H 2 metrics

We show the highest score from the newest CVSS version. Scores from different versions can't be compared, and the first score listed is sometimes a 0.0 placeholder.

VersionScoreBandVectorAssignerType
CVSS 3.1 7.5 HIGH CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H NVD Primary published
CVSS 2.0 5.0 none AV:N/AC:L/Au:N/C:N/I:N/A:P NVD Primary

Affected software and releases

Oracle advisories

AdvisoryTypeQuarterProducts Oracle names in its risk matrix
Oracle Critical Patch Update April 2021 ↗ CPU 2021-Q2 Oracle PeopleSoft / Application Server (SnakeYAML) (8.56, 8.57, 8.58)

Oracle components and versions

FamilyComponentVersions, as Oracle lists themRead as
Oracle PeopleSoft Application Server (SnakeYAML) 8.56, 8.57, 8.58 8.56 · 8.57 · 8.58

Maven packages

Affected and fixed versions, from OSV.dev
PackageIntroducedFixedLast affected
org.yaml:snakeyaml 0 1.26 unbounded

Products and versions

5 products, 8 version entries
SourceVendorProductSchemeAffected versions
nvd fedoraproject fedora generic 31 · 32
nvd oracle peoplesoft enterprise pt peopletools generic 8.56 · 8.57 · 8.58
osv org.yaml snakeyaml generic < 1.26
nvd quarkus quarkus generic ≤ 1.3.4
nvd snakeyaml project snakeyaml generic < 1.26

References

URLTags
https://lists.apache.org/thread.html/rcb2a7037366c58bac6aec6ce3df843a11ef97ae4eb049f05f410eaa5@%3Ccommon-commits.hadoop.apache.org%3E WEB
https://lists.apache.org/thread.html/rc3211c71f7e0973a1825d1988a3921288c06cd9d793eae97ecd34948@%3Ccommits.cassandra.apache.org%3E WEB
https://lists.apache.org/thread.html/rbaa1f513d903c89a08267c91d86811fa5bcc82e0596b6142c5cea7ea@%3Ccommits.cassandra.apache.org%3E WEB
https://lists.apache.org/thread.html/rb7b28ac741e32dd5edb2c22485d635275bead7290b056ee56baf8ce0@%3Cdev.atlas.apache.org%3E WEB
https://lists.apache.org/thread.html/rb5c33d0069c927fae16084f0605895b98d231d7c48527bcb822ac48c@%3Ccommits.cassandra.apache.org%3E WEB
https://lists.apache.org/thread.html/rb34d8d3269ad47a1400f5a1a2d8310e13a80b6576ebd7f512144198d@%3Ccommon-dev.hadoop.apache.org%3E WEB
https://lists.apache.org/thread.html/rb0e033d5ec8233360203431ad96580cf2ec56f47d9a425d894e279c2@%3Cpr.cassandra.apache.org%3E WEB
https://lists.apache.org/thread.html/raebd2019b3da8c2f90f31e8b203b45353f78770ca93bfe5376f5532e@%3Ccommon-issues.hadoop.apache.org%3E WEB
https://lists.apache.org/thread.html/r900e020760c89f082df1c6e0d46320eba721e4e47bb9eb521e68cd95@%3Ccommits.servicecomb.apache.org%3E WEB
https://lists.apache.org/thread.html/r8b57c57cffa01e418868a3c7535b987635ff1fb5ab534203bfa2d64a@%3Ccommits.pulsar.apache.org%3E WEB

Timeline

Published2019-12-12By the CVE Program.
NVD record modified2026-06-17NVD's own last-modified date for this record.