CVE-2026-48758 Details
Description
sigstore-js provides JavaScript libraries for interacting with Sigstore services. Prior to 3.2.1, the preAuthEncoding function in @sigstore/core uses Node.js ascii encoding when converting the PAE string to bytes, allowing payloadType to be mutated after signing without invalidating the signature and breaking the type-binding guarantee that DSSE is designed to provide. This issue is fixed in version 3.2.1.
A vulnerability exists in the Sigstore JavaScript library, specifically in the '@sigstore/core' package, prior to version 3.2.1. The issue arises in the 'preAuthEncoding' function, which incorrectly uses Node.js ASCII encoding to convert the Pre-Authentication Encoding (PAE) string into bytes. This flaw enables the 'payloadType' to be altered after signing without invalidating the signature, thereby undermining the type-binding guarantee intended by the DSSE specification. The vulnerability allows for the creation of identical PAE bytes and successful signature verification, despite the payloadType being mutated.
Users can upgrade to '@sigstore/core' version 3.2.1 or later, where this vulnerability has been fixed.
Metrics
CVSS 4.0 Severity and Vector Strings:
VolerionCVSS 3.x Severity and Vector Strings:
No data available for CVSS Version 2.0 on this CVE.
Volerion
Assessed Jul 14, 2026CISA-ADP
Assessed Jul 15, 2026References to Advisories, Solutions, and Tools
By selecting these links, you will be leaving this site. These are references gathered from the official CVE record and are not endorsed by Volerion.
| URL | Source(s) | Tag(s) |
|---|---|---|
| https://github.com/sigstore/sigstore-js/security/advisories/GHSA-jfc7-64v2-mr8c | CISA-ADP | AdvisoryExploitRemedyVendor |
| https://github.com/sigstore/sigstore-js/commit/b5aa4f1f8d2db0a9dfa6430fb114d9c2f1c304f7 | [email protected] | Source CodeVendor |
| https://github.com/sigstore/sigstore-js/pull/1657 | [email protected] | Source CodeVendor |
| https://github.com/sigstore/sigstore-js/releases/tag/%40sigstore%2Fcore%403.2.1 | [email protected] | Release NotesVendor |
| https://github.com/sigstore/sigstore-js/security/advisories/GHSA-jfc7-64v2-mr8c | [email protected] | AdvisoryExploitRemedyVendor |
Weakness Enumeration
| CWE-ID | CWE Name | Source |
|---|---|---|
| CWE-347 | Improper Verification of Cryptographic Signature | [email protected] |
Affected Products
| Product | Versions |
|---|---|
| sigstore-js | All versions |
CPE
Remediation
| |
| sigstore/core | <= 3.2.0 (semver) |
CPE
Remediation
| |
Change History
2 change records found show changes
| Date | Action | Recorded By |
|---|---|---|
| Jul 15, 2026 | CVE Modified | CISA-ADP |
| Jul 14, 2026 | New CVE Received | [email protected] |