Apache Fory: Deserialization of Untrusted Data
CVE-2025-61622 is a critical-severity deserialization of untrusted data 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. Affected Apache Fory versions: 0.12.0 through 0.12.2; 0.1.0 through 0.10.3. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 49% chance of exploitation within 30 days, which is in the top 1.1% of all scored CVEs.
Critical severity: a successful attack would have severe impact.
What to do
- Check which version of Apache Fory you run against the affected versions below, and install the vendor's latest release.
- 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 | 0.12.0 through 0.12.2; 0.1.0 through 0.10.3 | Not stated |
| Apache | Fory | 0.1.0 through 0.10.3; 0.12.0 through 0.12.2 | 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
- 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
Deserialization of untrusted data in python in pyfory versions 0.12.0 through 0.12.2, or the legacy pyfury versions from 0.1.0 through 0.10.3: allows arbitrary code execution. An application is vulnerable if it reads pyfory serialized data from untrusted sources. An attacker can craft a data stream that selects pickle-fallback serializer during deserialization, leading to the execution of `pickle.loads`, which is vulnerable to remote code execution. Users are recommended to upgrade to pyfory version 0.12.3 or later, which has removed pickle fallback serializer and thus fixes this issue.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Deserialization of Untrusted Data
The product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid.
How developers prevent this class of flaw
- If available, use the signing/sealing features of the programming language to assure that deserialized data has not been tainted. For example, a hash-based message authentication code (HMAC) could be used to ensure that data has not been modified.
- When deserializing data, populate a new object rather than just deserializing. The result is that the data flows through safe input validation and that the functions are safe.
- Explicitly define a final object() to prevent deserialization.
More Deserialization of Untrusted Data vulnerabilities (CWE-502)
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
Advisories
- lists.apache.org/thread/vfn9hp9qt06db5yo1gmj3l114o3o2csdIssue Tracking
Third-party and government advisories
- openwall.com/lists/oss-security/2025/09/29/3Mailing List, Third Party Advisory
Other vulnerabilities in Apache Fory
- 9.1 Critical severity
- 7.5 High severity
- 9.8 Critical severity
- 7.3 High severity
- 9.8 Critical severity
- 9.1 Critical severity
Recent Deserialization of Untrusted Data vulnerabilities
- 9.8 Critical severity
- 7.2 High severity
- 7.2 High severity
- 7.2 High severity
- 9.8 Critical severity
- 9.8 Critical severity
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