CVE-2026-62374SD JWT JS: Tampered disclosures silently dropped instead of rejected
- 7.1HighCVSS base score
- 0.23%Exploitation in 30 daysEPSS · top 87% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- YesPublic exploitsa reference or SSVC says so
Description
SD JWT JS is a JavaScript implementation of the Selective Disclosure JWT (SD-JWT) specification. In version 0.19.0 and earlier, `@sd-jwt/decode`, also used by `@sd-jwt/core`, silently drops a tampered Disclosure whose digest no longer matches the Issuer-signed `_sd` array and returns a reduced claim set, reporting success while the Issuer signature remains valid. Both a tampered Disclosure that remains valid JSON and a Disclosure containing invalid UTF-8 bytes reach this silent-drop behavior. In the latter case, the `TextDecoder / Buffer` decoding path substitutes U+FFFD replacement characters, recovering syntactically valid disclosure data instead of rejecting the malformed input. This violates RFC 9901 section 7.1 step 5, which requires rejection of unreferenced Disclosures, and section 7.1 step 3 / section 4.2.1, which require rejection of invalid Disclosures. A malicious holder can exploit this omission primitive, including through `SDJwtInstance.verify()` when key binding is required. An on-path attacker can also tamper with a Disclosure when the relying party does not enforce key binding; enforced key binding rejects on-path tampering because it invalidates the KB-JWT `sd_hash` binding. If the relying party defaults to allowing access when a constraining age, role, or restriction claim is absent, the silent claim reduction can change an authorization decision without an error. This issue is fixed in `@sd-jwt/core` version 0.20.0; no patched version of the standalone `@sd-jwt/decode` package is identified.
Public exploit
An exploit or proof of concept is public: anyone can try it against an unpatched system. A reference of the record is tagged as an exploit. CISA's SSVC rates its exploitation: a proof of concept is public.
Show the exploits1
References tagged exploit1 reference
Timeline
ID reserved
By GitHub_M
- 4 months later
· 4 months later
Published
- 6 days later
· 6 days later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 4.0 | High7.1 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N |
| NVDNVD · Deferred | 4.0 | High7.1 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
- EPSS (exploitation in 30 days)
- 0.23% · top 87% of all CVEs (14 Nov 2026)
- CISA SSVC
- Exploitation: poc · Automatable: yes · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.1.
Affected products
openwallet-foundation · @sd-jwt/core
- affected <= 0.19.0
openwallet-foundation · @sd-jwt/decode
- affected <= 0.19.0
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- npm@sd-jwt/coreGHSA-f9j6-8p6x-r9j6 (opens in a new tab)
- npm@sd-jwt/decodeGHSA-f9j6-8p6x-r9j6 (opens in a new tab)
References
References1
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-113215 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-f9j6-8p6x-r9j6 (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-62374)Record last updated .