Summary
Anchor: InterfaceAccount allows account substitution between unexpected types
References
Bug landed in: https://github.com/solana-foundation/anchor/pull/3837
Bug fixed in: https://github.com/solana-foundation/anchor/pull/4139
Impact
Any uses of InterfaceAccount allows another unexpected account type to be passed, after https://github.com/solana-foundation/anchor/pull/3837 disabled discriminator checking for this type.
The bug was originally reported and fixed in https://github.com/solana-foundation/anchor/pull/4139, see that PR for more details.
The application does not adequately validate input before processing it, allowing unexpected values to reach sensitive code paths. Typical impact: varies by context: data corruption, logic bypass, or denial of service.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
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https://github.com/solana-foundation/anchor/pull/4139 patched the issue and was released in 1.0.0-rc.2. Users should upgrade to the latest released version of Anchor 1.0.
Frequently Asked Questions
- What is GHSA-429Q-FHH4-R6HJ? GHSA-429Q-FHH4-R6HJ is a high-severity improper input validation vulnerability in anchor-lang (rust), affecting versions = 1.0.0-rc.1. It is fixed in 1.0.0-rc.2. The application does not adequately validate input before processing it, allowing unexpected values to reach sensitive code paths.
- Which versions of anchor-lang are affected by GHSA-429Q-FHH4-R6HJ? anchor-lang (rust) versions = 1.0.0-rc.1 is affected.
- Is there a fix for GHSA-429Q-FHH4-R6HJ? Yes. GHSA-429Q-FHH4-R6HJ is fixed in 1.0.0-rc.2. Upgrade to this version or later.
- Is GHSA-429Q-FHH4-R6HJ exploitable, and should I be worried? Whether GHSA-429Q-FHH4-R6HJ is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether GHSA-429Q-FHH4-R6HJ is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix GHSA-429Q-FHH4-R6HJ? Upgrade
anchor-langto 1.0.0-rc.2 or later.