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.
CVE-2026-48758
This medium-severity CVE scores 5.4 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.3%, top 82% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).
- Lower severity and no public exploit yet
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 5.4
- EG Score
- 5.4(medium)
- EG Risk
- 40(Track)EG Risk 40/100SSVC: Track
EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).
How it’s computedSeverity54% × 45%Exploitation40% × 40%Automatability0% × 15%Action: Routine — remediate on your standard cadence. - EPSS
- 18.1%
- KEV
- Not listed
Published
June 26, 2026
Last Modified
July 15, 2026
Advisory Details (3)
Auto-updated Jul 15, 2026DSSE payloadType type-binding failure · Advisory · sigstore/sigstore-js · GitHub
https://github.com/sigstore/sigstore-js/security/advisories/GHSA-jfc7-64v2-mr8cApply UTF-8 encoding to payload type during PAE calculation
Patch available: sigstore/sigstore-js @sigstore/mock@0.12.1 (PR #1657 merged 2026-05-22)
https://github.com/sigstore/sigstore-js/pull/1657commit b5aa4f1f8d2d (sigstore/sigstore-js)
Patch available: sigstore/sigstore-js @sigstore/mock@0.12.1 (contains commit b5aa4f1f8d2d)
https://github.com/sigstore/sigstore-js/commit/b5aa4f1f8d2db0a9dfa6430fb114d9c2f1c304f7Vendor Advisories for CVE-2026-48758(1)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
Affected Packages
(1 across 1 ecosystem)
npm(1)
| Package | Vulnerable range | Fixed in | Dependents |
|---|---|---|---|
| @sigstore/core | — | 3.2.1 | — |
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 9× in last 7d / 12× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
- 2026-07-23 14:18 UTCEPSS rescore
- 2026-07-23 03:18 UTCEG score recompute
- 2026-07-22 14:08 UTCEPSS rescore
- 2026-07-21 15:25 UTCEPSS rescore
- 2026-07-20 17:08 UTCEPSS rescore
- 2026-07-19 14:31 UTCEPSS rescore
- 2026-07-19 14:31 UTCEPSS rescore
- 2026-07-19 02:29 UTCEPSS rescore
- 2026-07-18 10:04 UTCEPSS rescore
- 2026-07-16 17:03 UTCEPSS rescore
- 2026-07-15 16:57 UTCEPSS rescore
- 2026-06-26 19:37 UTCEG score recompute
Related CVEs(same CWE)
Same CWE
10 shownCWE-347
Frequently asked(5)
What is CVE-2026-48758?
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Dependency Blast Radius
See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-48758
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