CyberSecBulletin
CVE-2022-40129NVD status: Modified

Foxit Reader: Use After Free

Published Updated By the CyberSecBulletin desk

CVE-2022-40129 is a high-severity use after free vulnerability in Foxit Reader 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 Reader versions: 12.0.1.12430. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 1.57% chance of exploitation within 30 days, higher than 76% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Check which version of Foxit Reader you run against the affected versions below, and install the vendor's latest release.
  2. 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

VendorProductAffected versionsFixed in
FoxitFoxit Reader12.0.1.12430Not stated
FoxitPDF Reader12.0.1.12430Not 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 NVD.

Scoring systemScoreSeverityScored by
CVSS 3.17.8HighNVD
CVSS 3.08.8HighCNA (cisco.com)

Official description

A use-after-free vulnerability exists in the JavaScript engine of Foxit Software's PDF Reader, version 12.0.1.12430. A specially-crafted PDF document can trigger the reuse of previously freed memory via misusing Optional Content Group API, which can lead to arbitrary code execution. An attacker needs to trick the user into opening the malicious file to trigger this vulnerability. Exploitation is also possible if a user visits a specially-crafted, malicious site if the browser plugin extension is enabled.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Use After Free

The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory belongs to the code that operates on the new pointer.

How developers prevent this class of flaw

  • Choose a language that provides automatic memory management.
  • When freeing pointers, be sure to set them to NULL once they are freed. However, the utilization of multiple or complex data structures may lower the usefulness of this strategy.

More Use After Free vulnerabilities (CWE-416)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: poc, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Technical write-ups (may include proof of concept)

Other vulnerabilities in Foxit Reader

All Foxit Reader vulnerabilities

Recent Use After Free vulnerabilities

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