CVE-2021-4437dbartholomae lambda-middleware frameguard JSON Mime-Type JsonDeserializer.ts redos
- 3.5LowCVSS base score
- 0.45%Exploitation in 30 daysEPSS · top 61% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- YesPublic exploitsa reference or SSVC says so
Description
A vulnerability, which was classified as problematic, has been found in dbartholomae lambda-middleware frameguard up to 1.0.4. Affected by this issue is some unknown functionality of the file packages/json-deserializer/src/JsonDeserializer.ts of the component JSON Mime-Type Handler. The manipulation leads to inefficient regular expression complexity. Upgrading to version 1.1.0 is able to address this issue. The patch is identified as f689404d830cbc1edd6a1018d3334ff5f44dc6a6. It is recommended to upgrade the affected component. VDB-253406 is the identifier assigned to this vulnerability.
Public exploit
An exploit or proof of concept is public: anyone can try it against an unpatched system. CISA's SSVC rates its exploitation: a proof of concept is public.
Timeline
ID reserved
By VulDB
- 1 day later
· 1 day later
Published
- 15 months later
· 15 months 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 |
|---|---|---|---|
| VulDBCNA (assigner) | 3.1 | Low3.5 | CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L |
| VulDBCNA (assigner) | 3.0 | Low3.5 | CVSS:3.0/AV:A/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L |
| VulDBCNA (assigner) | 2.0 | Low2.7 | AV:A/AC:L/Au:S/C:N/I:N/A:P |
| NVDNVD · Modified | 3.1 | Medium6.5 | CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 0.45% · top 61% of all CVEs (13 Nov 2026)
- CISA SSVC
- Exploitation: poc · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Low 3.5.
Affected products
dbartholomae · lambda-middleware frameguard
- affected 1.0.0
- affected 1.0.1
- affected 1.0.2
- affected 1.0.3
- affected 1.0.4
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- npm@lambda-middleware/json-deserializerGHSA-m3f4-957x-m785 (opens in a new tab)
References
References5
- https://vuldb.com/?id.253406 (opens in a new tab)vdb-entryx_transferred
- https://vuldb.com/?ctiid.253406 (opens in a new tab)signaturepermissions-requiredx_transferred
- https://github.com/dbartholomae/lambda-middleware/pull/57 (opens in a new tab)issue-trackingx_transferred
- https://github.com/dbartholomae/lambda-middleware/commit/f689404d830cbc1edd6a1018d3334ff5f44dc6a6 (opens in a new tab)patchx_transferred
- https://github.com/dbartholomae/lambda-middleware/releases/tag/%40lambda-middleware%2Fframeguard_v1.1.0 (opens in a new tab)patchx_transferred
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-2024-0667 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-m3f4-957x-m785 (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-2021-4437)Record last updated .