Security readout for executives and security teams
Plain-English summary
CVE-2020-36830 is a denial-of-service risk in nescalante urlregex up to 0.5.0. A crafted input can make the regular expression perform excessive backtracking, consuming processing time and reducing availability. Sources identify version 0.5.1 as the fixed release.
Executive priority
Treat this as a moderate availability risk. Prioritize remediation for internet-facing or multi-tenant services that parse user-supplied URLs or text with this library. It is less urgent than code execution flaws, but public exploit disclosure increases patching priority.
Technical view
The issue is CWE-1333 inefficient regular expression complexity in index.js, described as a Backtracking component problem. The CVSS v4.0 score is 5.3 with network reachability, low complexity, low privileges required, no user interaction, and low availability impact. The named patch is commit e5a085afe6abfaea1d1a78f54c45af9ef43ca1f9.
Likely exposure
Exposure is most likely in applications that include nescalante urlregex versions 0.1 through 0.5 and process attacker-controlled strings. Public-facing services are more relevant if untrusted input reaches this library. The source bundle does not identify specific downstream products.
Exploitation context
The sources state that an exploit has been publicly disclosed and may be used. They do not show CISA KEV listing or confirmed active exploitation. The CVSS vector indicates exploitation is remote but requires low privileges.
Researcher notes
The public record is narrow: affected package, versions, CWE, CVSS vector, public disclosure, and fixed release are identified. No source in the bundle confirms active exploitation, downstream affected products, or operational indicators beyond VulDB CTI references requiring permissions.
Mitigation direction
- Upgrade nescalante urlregex to version 0.5.1 or later.
- Confirm the patch commit is present if using a pinned fork.
- Update transitive dependency resolutions that keep urlregex at 0.5.0 or earlier.
- If immediate upgrade is blocked, check vendor guidance for supported mitigations.
Validation and detection
- Inventory direct and transitive use of nescalante urlregex.
- Flag versions 0.1, 0.2, 0.3, 0.4, and 0.5 as affected.
- Confirm whether attacker-controlled input can reach urlregex processing paths.
- Verify deployed artifacts use version 0.5.1 or include the named patch.
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.
CWE-1333: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2020-36830 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
- Medium
- CVSS
- 5.3 (4.0)
- Known Exploited
- No
- Published
Vector: 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
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 vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
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——Primary CVE scoreVulnerability scoring details
Base CVSS 4.0 score
5.3MediumVector: 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
Source materials
- CVE List V5 sourceCVE List V5
- VDB-276269 | nescalante urlregex Backtracking index.js redosCVE reference · vdb-entry
- VDB-276269 | CTI Indicators (IOB, IOC, TTP, IOA)CVE reference · signature, permissions-required
- https://github.com/nescalante/urlregex/pull/8CVE reference · exploit, issue-tracking
- https://github.com/nescalante/urlregex/commit/e5a085afe6abfaea1d1a78f54c45af9ef43ca1f9CVE reference · patch
- https://github.com/nescalante/urlregex/releases/tag/v0.5.1CVE reference · patch
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.