CVE-2018-18688 json
The Portable Document Format (PDF) specification does not provide any information regarding the concrete procedure of how to validate signa…
published 2021-01-07 5 y ago modified 2026-06-17 4 mo ago also EUVD-2018-10404
- cvss
- 5.3
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.1%
- EPSS 1.1% chance of exploitation in 30 days, percentile 66%
- public exploits
- 0
- none known
Summary
The Portable Document Format (PDF) specification does not provide any information regarding the concrete procedure of how to validate signatures. Consequently, an Incremental Saving vulnerability exists in multiple products. When an attacker uses the Incremental Saving feature to add pages or annotations, Body Updates are displayed to the user without any action by the signature-validation logic. This affects Foxit Reader before 9.4 and PhantomPDF before 8.3.9 and 9.x before 9.4. It also affects LibreOffice, Master PDF Editor, Nitro Pro, Nitro Reader, Nuance Power PDF Standard, PDF Editor 6 Pro, PDFelement6 Pro, PDF Studio Viewer 2018, PDF Studio Pro, Perfect PDF 10 Premium, and Perfect PDF Reader.
Patch / fix
- foxitsoftware phantompdf 9.4
Exploit prediction
1.15% chance of exploitation in the next 30 days, higher than 66% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N |
| NVD | 2.0 | 5.0 | AV:N/AC:L/Au:N/C:P/I:N/A:N |
Classification
- Weakness
-
- CWE-347 Improper Verification of Cryptographic Signature
References
-
foxitsoftware.com
/support/security-bulletins.php
vendor-advisory
-
pdf-insecurity.org
/signature/evaluation_2018.html
third-party-advisory
-
pdf-insecurity.org
/signature/signature.html
third-party-advisory
-
pdfa.org
/recently-identified-pdf-digital-signature-vulnerabilities/
third-party-advisory
Sources
- CVE List CVE-2018-18688
- NVD CVE-2018-18688
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