CVE-2019-18426: WhatsApp Cross-Site Scripting Vulnerability

Reference page built from the source records below, each shown as its source publishes it. Dataset version ref-1c429c26714f, updated 2026-11-02T23:39:54.475Z.

CISA Known Exploited Vulnerabilities

Name: WhatsApp Cross-Site Scripting Vulnerability
Vendor: Meta Platforms
Product: WhatsApp
Added to the catalog: 2022-05-23
Due date for US federal agencies: 2022-06-13
Weaknesses: CWE-79
Catalog version: 2026.10.30

A vulnerability in WhatsApp Desktop when paired with WhatsApp for iPhone allows cross-site scripting and local file reading.

Required action (CISA)

Apply updates per vendor instructions.

Ransomware use: CISA does not mark known use of this vulnerability in ransomware campaigns.

Links in CISA's notes

https://nvd.nist.gov/vuln/detail/CVE-2019-18426

Read on 2026-11-02T23:39:54.475Z under licence cisa-kev-cc0@b0067899 from https://www.cisa.gov/sites/default/files/feeds/known_exploited_vulnerabilities.json

NVD analysis

Status: Analyzed
Published: 2020-01-21T21:15:16.147
Last modified: 2026-06-17T02:25:01.227
Weaknesses: CWE-79

A vulnerability in WhatsApp Desktop versions prior to 0.3.9309 when paired with WhatsApp for iPhone versions prior to 2.20.10 allows cross-site scripting and local file reading. Exploiting the vulnerability requires the victim to click a link preview from a specially crafted text message.

Metric	Score	Severity	Vector	Scored by
CVSS 3.1	8.2	HIGH	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:L/A:N	[email protected] (Primary)
CVSS 3.1	8.2	HIGH	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:L/A:N	134c704f-9b21-4f2e-91b3-4a467353bcc0 (Secondary)
CVSS 2.0	5.8	MEDIUM	AV:N/AC:M/Au:N/C:P/I:P/A:N	[email protected] (Primary)

References

http://packetstormsecurity.com/files/157097/WhatsApp-Desktop-0.3.9308-Cross-Site-Scripting.html (Exploit, Third Party Advisory, VDB Entry)
https://www.facebook.com/security/advisories/cve-2019-18426 (Vendor Advisory)
http://packetstormsecurity.com/files/157097/WhatsApp-Desktop-0.3.9308-Cross-Site-Scripting.html (Exploit, Third Party Advisory, VDB Entry)
https://www.facebook.com/security/advisories/cve-2019-18426 (Vendor Advisory)
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2019-18426 (US Government Resource)

This product uses the NVD API but is not endorsed or certified by the NVD.

Read on 2026-11-02T23:41:43.468Z under licence nvd-api-terms-of-use@ff2a5288 from https://services.nvd.nist.gov/rest/json/cves/2.0?cveId=CVE-2019-18426

CVE record

Assigner: facebook
State: PUBLISHED
Published: 2020-01-21T20:30:15.000Z
Updated: 2025-10-21T23:35:53.174Z
Problem types: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') (CWE-79)

References

https://www.facebook.com/security/advisories/cve-2019-18426
http://packetstormsecurity.com/files/157097/WhatsApp-Desktop-0.3.9308-Cross-Site-Scripting.html

Read on 2026-11-03T01:01:47.984Z under licence cve-terms-of-use@81bfa2f3 from https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2019/18xxx/CVE-2019-18426.json

Defensive techniques (MITRE D3FEND)

D3FEND maps these defensive techniques to the weakness (CWE) that NVD lists for this CVE, through the digital artifacts the weakness affects. D3FEND does not say they stop this vulnerability.

CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Harden: Trusted Library (acts on Subroutine)
Harden: Variable Initialization (acts on Subroutine)
Isolate: Application-based Process Isolation (acts on Subroutine)
Harden: Software Update (acts on Software)
Harden: Domain Logic Validation (acts on Subroutine)
Harden: Credential Scrubbing (acts on Subroutine)
Restore: Restore Software (acts on Software)
Model: Asset Vulnerability Enumeration (acts on Software)
Model: Software Inventory (acts on Software)

D3FEND ontology version 1.6.0.

Read on 2026-11-02T23:54:18.062Z under licence d3fend-terms-of-use@f98cbc7e from https://d3fend.mitre.org/api/weakness/cwe/CWE-79.json

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Sources and licences

CISA
Source: CISA Catalog of Known Exploited Vulnerabilities, version 2026.10.30, CC0 1.0. Use of this data does not imply endorsement by CISA or DHS.
CC0 1.0 Universal
National Vulnerability Database (NIST)
This product uses the NVD API but is not endorsed or certified by the NVD.
NVD API Terms of Use (NIST publications in the public domain, 17 U.S.C. 105)
CVE Program, The MITRE Corporation
Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation. CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy.
CVE Program Terms of Use ("CVE Usage" licence)
MITRE D3FEND
MITRE D3FEND™ knowledge graph. © 2025 The MITRE Corporation.
"The MITRE Corporation (MITRE) hereby grants you a non-exclusive, royalty-free license to use D3FEND for research, development, and commercial purposes. Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy." Terms: https://d3fend.mitre.org/tou/
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Cite this page

Dragons Eye Ransomware Tracker, "CVE-2019-18426: WhatsApp Cross-Site Scripting Vulnerability",
entity page, dataset version ref-1c429c26714f, updated 2026-11-02T23:39:54.475Z,
https://ransomware-tracker.com/cve/CVE-2019-18426 (accessed 2026-11-03).
Underlying source: CISA Catalog of Known Exploited Vulnerabilities, version 2026.10.30.
Underlying source: National Vulnerability Database (NIST), CVE API 2.0, record last modified 2026-06-17T02:25:01.227.
Underlying source: CVE List (CVE Program, The MITRE Corporation), record updated 2025-10-21T23:35:53.174Z.
Underlying source: MITRE D3FEND, ontology version 1.6.0.

Pages change. The dataset version identifies the data, but no archive of old versions is kept, so this citation cannot be replayed later.

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