Foxit PDF Editor: External Control of File Name or Path
CVE-2026-91797 is a high-severity external control of file name or path 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 2026.2 and earlier; Versions 14.0.7 and earlier; Versions 13.2.6 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 0.35% 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 2026.2 and earlier; Versions 14.0.7 and earlier; Versions 13.2.6 and earlier | Not stated |
| Foxit Software | Foxit PDF Reader | Versions 2026.2 and earlier | Not stated |
| Foxit | PDF Editor | 13.2.5.63482 and earlier; 14.0.0.33046 through 14.0.7.33751; 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 2026.2.0.39747 | Not stated |
| Foxit | PDF Reader | 2026.2.0.39747 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
Foxit PDF Editor/Reader failed to validate the directory traversal path in the attachment file name, resulting in malicious attachments being able to be written to directories outside the expected secure area when the PDF is opened.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: External Control of File Name or Path
The product allows user input to control or influence paths or file names that are used in filesystem operations.
How developers prevent this class of flaw
- When the set of filenames is limited or known, create a mapping from a set of fixed input values (such as numeric IDs) to the actual filenames, and reject all other inputs. For example, ID 1 could map to inbox.txt and ID 2 could map to profile.txt. Features such as the ESAPI AccessReferenceMap provide this capability.
- Run your code in a jail or similar sandbox environment that enforces strict boundaries between the process and the operating system. This may effectively restrict all access to files within a particular directory. Examples include the Unix chroot jail and AppArmor. In general, managed code may provide some protection. This may not be a feasible solution, and it only limits the impact to the operating system; the rest of your application may still be subject to compromise. Be careful to avoid CWE-243 and other weaknesses related to jails.
- For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.
More External Control of File Name or Path vulnerabilities (CWE-73)
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 External Control of File Name or Path vulnerabilities
- 7.2 High severity
- 8.4 High severity
- 8.8 High severity
- 8.3 High severity
- 9.8 Critical severity
- 8.1 High severity
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