Foxit PDF Editor: Improper Validation of Array Index
CVE-2026-57251 is a high-severity improper validation of array index vulnerability in Foxit PDF Editor from Foxit, with a CVSS 3.1 base score of 7.8 out of 10. It can be exploited with local access to the system by an unauthenticated attacker, but only if a user takes part, for example by opening a link or file. Affected Foxit PDF Editor versions: Versions 2026.1.1 and earlier; Versions 14.0.4 and earlier; Versions 13.2.4 and earlier. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.17% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Check which version of Foxit PDF Editor you run against the affected versions below, and install the vendor's latest release.
- Read the advisory on foxit.com for workarounds and exact fixed builds.
- Because the attack needs a user to take part, warn users about unexpected links and files related to this product until it is patched.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Foxit Software | Foxit PDF Editor | Versions 2026.1.1 and earlier; Versions 14.0.4 and earlier; Versions 13.2.4 and earlier | Not stated |
| Foxit Software | Foxit PDF Reader | Versions 2026.1.1 and earlier | Not stated |
| Foxit | PDF Editor | 13.2.4.24048 and earlier; 14.0.0.33046 through 14.0.4.33508; 2023.1.0.15510 through 2023.3.0.23028; 2024.1.0.23997 through 2024.4.1.27687; 2025.1.0.27937 through 2025.3.0.35737; 2026.1.0.36452 through 2026.1.1.36485 | Not stated |
| Foxit | PDF Reader | 2026.1.1.36485 and earlier | Not stated |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- LocalThe attacker needs local access or must trick a user into running something.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- RequiredA user must take an action such as opening a file or link.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H. Scored by CNA.
Official description
The application opens a PDF, but the cloud-like appearance of the construction process lacks proper setting of an upper limit and consistency checks. Out-of-bounds access to the underlying array is exposed, ultimately leading to a crash of the application.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Validation of Array Index
The product uses untrusted input when calculating or using an array index, but the product does not validate or incorrectly validates the index to ensure the index references a valid position within the array.
How developers prevent this class of flaw
- Use an input validation framework such as Struts or the OWASP ESAPI Validation API. Note that using a framework does not automatically address all input validation problems; be mindful of weaknesses that could arise from misusing the framework itself (CWE-1173).
- Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, Ada allows the programmer to constrain the values of a variable and languages such as Java and Ruby will allow the programmer to handle exceptions when an out-of-bounds index is accessed.
- Use a CPU and operating system that offers Data Execution Protection (using hardware NX or XD bits) or the equivalent techniques that simulate this feature in software, such as PaX. These techniques ensure that any instruction executed is exclusively at a memory address that is part of the code segment. For more information on these techniques see D3-PSEP (Process Segment Execution Prevention) from D3FEND.
More Improper Validation of Array Index vulnerabilities (CWE-129)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Other vulnerabilities in Foxit PDF Editor
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
- 8.1 High severity
- 7.8 High severity
- 7.8 High severity
Recent Improper Validation of Array Index vulnerabilities
- 8.3 High severity
- 8.3 High severity
- 8.3 High severity
- 8.3 High severity
- 8.3 High severity
- 8.3 High severity
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