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CVE-2023-482235.9MediumCWE-20

CVE-2023-48223: fast-jwt JWT Algorithm Confusion

nearform · fast-jwt

Affected: nearform fast-jwt · Exploitation: unlikely (under 1%)

Not in CyberSIXT coverage yet: no article names this CVE. This page shows the public record.

0.7%probability of exploitation in the next 30 days
53rd percentile
050100

Higher than 53% of scored CVEs

5.9MediumCVSS 3.1
LowMedium

DescriptionCVE.org

fast-jwt provides fast JSON Web Token (JWT) implementation. Prior to version 3.3.2, the fast-jwt library does not properly prevent JWT algorithm confusion for all public key types. The 'publicKeyPemMatcher' in 'fast-jwt/src/crypto.js' does not properly match all common PEM formats for public keys. To exploit this vulnerability, an attacker needs to craft a malicious JWT token containing the HS256 algorithm, signed with the public RSA key of the victim application. This attack will only work if the victim application utilizes a public key containing the `BEGIN RSA PUBLIC KEY` header. Applications using the RS256 algorithm, a public key with a `BEGIN RSA PUBLIC KEY` header, and calling the verify function without explicitly providing an algorithm, are vulnerable to this algorithm confusion attack which allows attackers to sign arbitrary payloads which will be accepted by the verifier. Version 3.3.2 contains a patch for this issue. As a workaround, change line 29 of `blob/master/src/crypto.js` to include a regular expression.

Affected products1

From the CVE record. A product or version that is not listed is unknown, not unaffected.

  • nearform · fast-jwt< 3.3.2

On the Atlas

Every published CVE is on the CyberSIXT Atlas, grouped by weakness, vendor and month.

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Exploitation
Unlikely (under 1%). EPSS under 1%, or no score yet.
CISA KEV
Not listed
Public check
No public nuclei template
Vendor
nearform
Published
November 2023

CoverageNo articles yet

No CyberSIXT article names CVE-2023-48223 yet, so there is no coverage timeline, action brief or change log for it. Everything on this page comes from the public CVE record, CISA KEV, EPSS and the nuclei template index. Search the archive or see the CVEs in the news.

References