(0Day) Meta fairseq load_ema_from_checkpoint Deserialization of Untrusted Data Remote Code Execution Vulnerability
Vulnerability Details
This vulnerability allows remote attackers to execute arbitrary code on affected installations of Meta fairseq. User interaction is required to exploit this vulnerability in that the target must visit a malicious page or open a malicious file.
The specific flaw exists within the load_ema_from_checkpoint method. The issue results from the lack of proper validation of user-supplied data, which can result in deserialization of untrusted data. An attacker can leverage this vulnerability to execute code in the context of the current process.
Additional Details
03/04/26 - ZDI reported the vulnerability to the vendor
03/05/26 - the vendor acknowledged the receipt of the report
03/17/26 - the vendor communicated that the report was being investigated
04/07/26 - the vendor communicated that the fairseq repository is no longer maintained and was archived on March 20, 2024. However, GitHub shows the repository was actually archived on March 20, 2026, after this report was submitted https://github.com/facebookresearch/fairseq
10/23/26 - ZDI notified the vendor of the intention to publish the case as a 0-day advisory
-- Mitigation: Given the nature of the vulnerability, the only salient mitigation strategy is to restrict interaction with the product
Disclosure Timeline
- 2026-03-04 - Vulnerability reported to vendor
- 2026-11-11 - Coordinated public release of advisory
- 2026-11-11 - Advisory Updated
Credit
Bongeun Koo (@kiddo_pwn)
