Security readout for executives and security teams
Plain-English summary
This vulnerability affects Inversoft prime-jwt before the stated fixing commit. A crafted JWT could be incorrectly accepted because signature validation may mishandle a token declaring the “none” algorithm. If the library protects sessions, API access, or identity assertions, this can undermine authentication decisions.
Executive priority
Treat as high priority where prime-jwt supports login, session, or API authorization. If the library is absent or used only for non-security parsing, business urgency is lower.
Technical view
CVE-2018-1000531 is described as CWE-20 input validation weakness in JWTDecoder.decode. The issue can result in incorrect JWT signature validation when processing an attacker-controlled token with a valid header using algorithm “none.” The source says it was fixed after commit abb0d479389a2509f939452a6767dc424bb5e6ba.
Likely exposure
Exposure is limited to applications using vulnerable Inversoft prime-jwt versions before the fixing commit, especially where JWTDecoder.decode validates user-supplied tokens for authentication or authorization.
Exploitation context
The bundle does not cite active exploitation, and the CVE is not marked KEV. The described attack requires an application to process a crafted JWT and rely on the vulnerable validation result.
Researcher notes
Public details are sparse: no CVSS vector, no detailed affected version list, and no exploit evidence in the bundle. Analysis should focus on dependency presence, JWTDecoder.decode usage, and whether security decisions trust its validation result.
Mitigation direction
- Inventory applications and services using Inversoft prime-jwt.
- Upgrade to a prime-jwt version containing the fix after the cited commit.
- Check vendor or maintainer guidance for any release-specific remediation.
- Ensure JWT validation only allows expected signing algorithms.
- Prioritize internet-facing authentication and API services first.
Validation and detection
- Review dependency manifests and lockfiles for prime-jwt usage.
- Confirm deployed versions include the fix after the cited commit.
- Identify code paths using JWTDecoder.decode on user-controlled tokens.
- Verify unsigned or unexpected-algorithm JWTs are rejected in safe testing.
- Review authentication logs for suspicious JWT algorithm values if logged.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
Credential and access behavior lookup
The CVE wording references authentication or credential exposure, so valid-account and credential-access review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2018-1000531 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Unknown
- CVSS
- Not scored
- Known Exploited
- No
- Published
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS and timeline data
No CVSS vectors or timeline events were available in the normalized CVE source material.
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/inversoft/prime-jwt/issues/3CVE reference · x_refsource_MISC
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.