vciy

CVE-2017-18640

INDEX BUILT · 2026-09-20

No source can show you its own past. This one can.

Print this page to keep the view as it stands on this date. Everything hidden behind a disclosure opens, and every receipt prints with its value.

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

CVE-2017-186403 of 4 sources documented this
33

rank 33 = 7 + 19 + 0 + 7 + 0

rank@v1 · scheduled

Someone is already using it

CISA KEV catalog · public proof-of-concept · FIRST EPSS

EPSS 0.26723  ·  without this subject the record ranks 26

What it costs you if it fires

NVD CVSS base score, then the CNA's own

CVSS 7.5, from NVD  ·  without this subject the record ranks 14

It is getting worse, not staying still

FIRST EPSS series, rescorings and bad loads removed

no persisting rise in 365 days  ·  without this subject the record ranks 33

How much of the world it touches

NVD CPE configurations

7 products in the CPE ranges  ·  without this subject the record ranks 26

Someone else already set the date

CISA KEV remediation due date

no CISA due date  ·  without this subject the record ranks 33

Unaudited dollar value2 of 3 inputs carry a receipt
Exposure$816,000over the next 30 days, if this record is yours
Movement-$250,000on 2022-02-04, the last material move, 4 years, 4 months before this reading
Basisassumeda published average, not your estate

$816,000 = $4.99M incident cost x 0.6121449559255632 exposure x 0.26723 likelihood

udv@v1 · unaudited · wrong for you until you say what you run

$4.99M is the cost of a breach that happened, from IBM Cost of a Data Breach Report 2026, global average. It is not the value of any asset of yours. That average already covers breaches of every severity, so scaling it by exposure understates a partial-impact record. That is an assumption, not a measurement. Your own asset value goes in the decision record.

Hindsight · the state

0.26723EPSSNOT IN KEVas of 2026-09-20
Severity7.5 HIGHreceipt
Harmunauthenticated · networkreceipt
Exploitationnone in held sources
Defenseunaffected versions publishedreceipt
Movementthreshold crossedreceipt
RISING10Risen from 0.09302 to 0.26723 across 26 observations. arc-rules@v1

Foresight · where to check next

No weakness class or product neighbourhood is held for this record, so this index cannot name anywhere to check next. That is an absence in the record, not a finding about the software.

Color is a claim, not decoration:the hostile worldthe defenseno signal

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Harm, if it fires from the vector and the weakness

Written for the ticket you're about to file.

Reachnetwork-reachable · no privileges required · no user interaction · low attack complexityreceipt
ImpactComplete availability lossreceipt
Scored fromCVSS v3.1 · NVD's vectorreceipt
Weakness classCWE-776 Improper Restriction of Recursive Entity References in DTDs ('XML Entity Expansion')receipt
Published consequencesCWE-776: Availability: DoS: Resource Consumption (Other)[email protected]

CISA KEV & Federal Remediation Deadline from the record and CISA

The fix, and how long it's been waiting.

First unaffected version, by branchproject snakeyaml 1.26receipt
Patch available sinceNo dated patch-availability record in held sources. The index holds reference URLs without dates and only the current revision of the CVE record, so the day a fix first existed cannot be derived. Only the versions it landed in.

Exploit Status & Known PoCs a ladder, not a score

Current rung: Nothing observed in held sources.

  • RUNG 1Nothing observed in held sources
  • RUNG 2Proof-of-concept published
  • RUNG 3Exploited in the wild · CISA KEV listed
  • RUNG 4Ransomware campaign use known

Authority who says so

CVSS, NVD7.5 HIGHreceipt
Exploit probability0.26723 · top 2% of all CVEsreceipt
Blast breadth4 products across 4 vendorsderived
Assigned bymitrereceipt
Recorded changes26 · last 19 Sep 2026derived

Affected & Fixed Versions as published

Named in the CPE rangesSnakeyaml project snakeyaml; Oracle peoplesoft enterprise pt peopletools; Fedoraproject fedora; and 1 morereceipt
Published rangessnakeyaml project snakeyaml < 1.26; fedoraproject fedora 31; fedoraproject fedora 32; quarkus <= 1.3.4receipt
Show all 7 published ranges
snakeyaml project snakeyaml < 1.26
fedoraproject fedora 31
fedoraproject fedora 32
quarkus <= 1.3.4
oracle peoplesoft enterprise pt peopletools 8.56
oracle peoplesoft enterprise pt peopletools 8.57
oracle peoplesoft enterprise pt peopletools 8.58

A rung lights from a row in the index, never from an assessment. "Held sources" is the true scope of the claim: this index reads the CVE record, NVD, CISA KEV, FIRST's EPSS and public proof-of-concept repositories, and it does not observe attacks.

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What it is stated by the CNA

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

NVD's analysis a second authority

severity
7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
weakness
CWE-776
affected versions
snakeyaml project snakeyaml < 1.26; fedoraproject fedora 31; fedoraproject fedora 32; and 4 more, listed in full below

check it yourself lists.fedoraproject.org lists.fedoraproject.org lists.apache.org lists.apache.org lists.apache.org lists.apache.org +14 morereceipt

Dated events

2021-06-19EPSS moved 0.10 to 0.332026-06-15EPSS moved 0.04 to 0.27

Movement the material steps

14 Apr 20210.09302
19 Jun 20210.33281 · crossed 0.10
24 Jun 20210.10005
4 Feb 20220.02686 · crossed 0.10
7 Mar 20230.00806 · scoring model v2023.03.01
17 Mar 20250.02176 · scoring model v2025.03.14
15 Jun 20260.26723 · crossed 0.10 · scoring model v2026.06.15

This score more than doubled inside 72 hours. Both observations are in the full history below.

Show all 26 observations
14 Apr 20210.09302
20 Apr 20210.09655
15 Jun 20210.0983
19 Jun 20210.33281
24 Jun 20210.10005
7 Oct 20210.10179
9 Oct 20210.10869
4 Feb 20220.02686
7 Mar 20230.00806
22 May 20230.00871
8 Jul 20230.00660
8 Nov 20230.01874
5 Dec 20240.02065
17 Dec 20240.01859
17 Mar 20250.02176
18 Mar 20250.02225
29 Mar 20250.09231
30 Mar 20250.02225
31 Mar 20250.02166
15 Apr 20250.02225
17 Apr 20250.02166
25 Jun 20250.02766
9 Jul 20250.02166
5 May 20260.02766
13 Jun 20260.03605
15 Jun 20260.26723

26 observations held. A highlighted step crossed a promotion threshold. A step marked with a scoring model moved because the instrument was replaced, not because the vulnerability changed. receipt

The full biography

EPSS 0.26723Published2019-12-12Index as of2026-06-15

Exploit probability more than doubled between 2026-06-13 and 2026-06-15 (0.03605 → 0.26723) and the record had been public for 6 years, 6 months when this index was last written.

Published 2019-12-12 receipt · Index as of 2026-06-15 derived

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