CVE-2020-36830nescalante urlregex Backtracking index.js redos
- 5.3MediumCVSS base score
- 0.80%Exploitation in 30 daysEPSS · top 43% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- YesPublic exploitsa reference or SSVC says so
Description
A vulnerability was found in nescalante urlregex up to 0.5.0 and classified as problematic. This issue affects some unknown processing of the file index.js of the component Backtracking. The manipulation leads to inefficient regular expression complexity. The attack may be initiated remotely. The exploit has been disclosed to the public and may be used. Upgrading to version 0.5.1 is able to address this issue. The identifier of the patch is e5a085afe6abfaea1d1a78f54c45af9ef43ca1f9. It is recommended to upgrade the affected component.
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
- https://github.com/nescalante/urlregex/pull/8 (opens in a new tab)exploitissue-tracking
Timeline
ID reserved
By VulDB
- 2 days later
· 2 days later
Published
- 1 day later
· 1 day 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) | 4.0 | Medium5.3 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N |
| VulDBCNA (assigner) | 3.1 | Medium4.3 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L |
| VulDBCNA (assigner) | 3.0 | Medium4.3 | CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L |
| VulDBCNA (assigner) | 2.0 | Medium4.0 | AV:N/AC:L/Au:S/C:N/I:N/A:P |
| NVDNVD · Analyzed | 4.0 | Medium5.3 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/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)
- 0.80% · top 43% of all CVEs (15 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: Medium 5.3.
Affected products
- affected 0.1
- affected 0.2
- affected 0.3
- affected 0.4
- affected 0.5
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- npmurlregexGHSA-rw72-v6c7-hf9r (opens in a new tab)
References
References5
- VDB-276269 | nescalante urlregex Backtracking index.js redos (opens in a new tab)vdb-entry
- VDB-276269 | CTI Indicators (IOB, IOC, TTP, IOA) (opens in a new tab)signaturepermissions-required
- https://github.com/nescalante/urlregex/pull/8 (opens in a new tab)exploitissue-tracking
- https://github.com/nescalante/urlregex/commit/e5a085afe6abfaea1d1a78f54c45af9ef43ca1f9 (opens in a new tab)patch
- https://github.com/nescalante/urlregex/releases/tag/v0.5.1 (opens in a new tab)patch
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-2024-2870 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-rw72-v6c7-hf9r (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-2020-36830)Record last updated .