CVE-2025-62375 go-witness Improper Verification of AWS EC2 Identity Documents
Attackers can bypass AWS EC2 identity verification in go-witness by supplying forged documents, leading to incorrect trust decisions in attestation workflows.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2025-62375?
CVE-2025-62375 is a medium-severity vulnerability in in-toto go-witness, published on 15 Oct 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
go-witness and witness are Go modules for generating attestations. In go-witness versions 0.8.6 and earlier and witness versions 0.9.2 and earlier the AWS attestor improperly verifies AWS EC2 instance identity documents. Verification can incorrectly succeed when a signature is not present or is empty, and when RSA signature verification fails. The attestor also embeds a single legacy global AWS public certificate and does not account for newer region specific certificates issued in 2024, making detection of forged documents difficult without additional trusted region data. An attacker able to supply or intercept instance identity document data (such as through Instance Metadata Service impersonation) can cause a forged identity document to be accepted, leading to incorrect trust decisions based on the attestation. This is fixed in go-witness 0.9.1 and witness 0.10.1. As a workaround, manually verify the included identity document, signature, and public key with standard tools (for example openssl) following AWS’s verification guidance, or disable use of the AWS attestor until upgraded.
Weakness: CWE-295
Which versions are affected by CVE-2025-62375?
3 open source packages ship an affected version, including github.com/in-toto/go-witness.
| Package | Affected | Fixed in |
|---|---|---|
github.com/in-toto/go-witness Go | All versions | 0.9.1 |
github.com/in-toto/go-witness Go | All versions | 0.9.1 |
github.com/in-toto/go-witness Go | All versions | 0.9.1 |
How do I fix CVE-2025-62375?
Upgrade github.com/in-toto/go-witness to 0.9.1 or later.
Is CVE-2025-62375 being exploited?
There is no known exploitation of CVE-2025-62375 in the wild and no public exploit code.
Sources
Also known as CLEANSTART-2026-AQ99839, CLEANSTART-2026-EU40217, GHSA-72c7-4g63-hpw5, GO-2025-4028.