Apache Fory: Access of Resource Using Incompatible Type
CVE-2026-71558 is a critical-severity access of resource using incompatible type vulnerability in Apache Fory from Apache, with a CVSS 3.1 base score of 9.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists version 1.5.0 as the first without the flaw, so updating Apache Fory to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.99% chance of exploitation within 30 days, higher than 63% of scored CVEs.
Critical severity: a successful attack would have severe impact.
What to do
- Update Apache Fory to 1.5.0 or a later version.
- Update Fory to 1.5.0 or a later version.
- Read the advisory on lists.apache.org for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Apache | Apache Fory | 0.14.0 up to, but not including, 1.5.0 | 1.5.0 |
| Apache | Fory | 0.14.0 up to, but not including, 1.5.0 | 1.5.0 |
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
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- 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:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by CISA (ADP).
Official description
Heap type confusion vulnerability in Apache Fory C++ deserialization. This issue affects Apache Fory C++ versions from 0.14.0 before 1.5.0. A crafted input payload can bypass type compatibility checks during polymorphic smart-pointer deserialization, causing an object of an incompatible type to be treated as the declared base type. This may result in undefined behavior and potentially lead to denial of service or arbitrary code execution. Users are recommended to upgrade to Apache Fory 1.5.0, which fixes this issue. Applications not using Apache Fory C++ polymorphic smart-pointer deserialization are not affected.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Access of Resource Using Incompatible Type
The product allocates or initializes a resource such as a pointer, object, or variable using one type, but it later accesses that resource using a type that is incompatible with the original type.
More Access of Resource Using Incompatible Type vulnerabilities (CWE-843)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Advisories
Third-party and government advisories
- openwall.com/lists/oss-security/2026/08/07/3Mailing List, Third Party Advisory
Other vulnerabilities in Apache Fory
- 9.1 Critical severity
- 7.5 High severity
- 7.3 High severity
- 9.8 Critical severity
- 9.1 Critical severity
- 9.8 Critical severity
Recent Access of Resource Using Incompatible Type vulnerabilities
- 7.2 High severity
- 8.8 High severity
- 9.6 Critical severity
- 8.8 High severity
- 7.5 High severity
- 8.8 High severity
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