CVE-2022-23649
What it is
Cosign provides container signing, verification, and storage in an OCI registry for the sigstore project. Prior to version 1.5.2, Cosign can be manipulated to claim that an entry for a signature exists in the Rekor transparency log even if it doesn't. This requires the attacker to have pull and push permissions for the signature in OCI. This can happen with both standard signing with a keypair and "keyless signing" with Fulcio. If an attacker has access to the signature in OCI, they can manipulate cosign into believing the entry was stored in Rekor even though it wasn't. The vulnerability has been patched in v1.5.2 of Cosign. The `signature` in the `signedEntryTimestamp` provided by Rekor is now compared to the `signature` that is being verified. If these don't match, then an error is returned. If a valid bundle is copied to a different signature, verification should fail. Cosign output now only informs the user that certificates were verified if a certificate was in fact verified. There is currently no known workaround.
At a glance
- Exploitability
- Can be exploited locally on the machine with a low-privilege account. Limited direct impact.
- Exploit odds
- 0.2% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.2% in the next 30 days (EPSS).
- Severity: 3.3 LOW (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.2% · EPSS, next 30 days
- Weakness
- CWE-295 · Improper certificate validation
- Record status
- Modified
Affected
- Sigstore Cosign < 1.5.2
Attack profile CVSS 3.1 · 3.3
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- Low
- Availability
- None
Raw vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2022-23649.md and follow it. Check whether this project is affected by CVE-2022-23649. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://github.com/sigstore/cosign/commit/96d410a6580e4e81d24d112a0855c70ca3fb5b49
- https://github.com/sigstore/cosign/security/advisories/GHSA-ccxc-vr6p-4858
- https://github.com/sigstore/cosign/commit/96d410a6580e4e81d24d112a0855c70ca3fb5b49
- https://github.com/sigstore/cosign/security/advisories/GHSA-ccxc-vr6p-4858
References
- https://github.com/sigstore/cosign/commit/96d410a6580e4e81d24d112a0855c70ca3fb5b49
- https://github.com/sigstore/cosign/security/advisories/GHSA-ccxc-vr6p-4858
- https://github.com/sigstore/cosign/commit/96d410a6580e4e81d24d112a0855c70ca3fb5b49
- https://github.com/sigstore/cosign/security/advisories/GHSA-ccxc-vr6p-4858