CVE-2021-23387 json
Open Redirect
published 2021-05-24 5 y ago modified 2026-07-08 4 mo ago also GHSA-rfhr-62xp-2fp2 , EUVD-2021-1397
- cvss
- 5.4
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.1%
- EPSS 1.1% chance of exploitation in 30 days, percentile 67%
- public exploits
- 0
- none known
Summary
The package trailing-slash before 2.0.1 are vulnerable to Open Redirect via the use of trailing double slashes in the URL when accessing the vulnerable endpoint (such as https://example.com//attacker.example/). The vulnerable code is in index.js::createTrailing(), as the web server uses relative URLs instead of absolute URLs.
Patch / fix
- npm trailing-slash 2.0.1
- n/a trailing-slash 2.0.1
Exploit prediction
1.15% chance of exploitation in the next 30 days, higher than 67% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- snyk.io https://snyk.io/vuln/SNYK-JS-TRAILINGSLASH-1085707 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 5.4 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N/E:P/RL:O/RC:C |
| CNA | 3.1 | 5.4 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N |
| NVD | 3.1 | 6.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N |
| NVD | 2.0 | 5.8 | AV:N/AC:M/Au:N/C:P/I:P/A:N |
| GitHub | 3.1 | 5.4 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| npm | trailing-slash | <2.0.1 |
2.0.1 |
Affected products
- n/a trailing-slash
Classification
- Weakness
-
- CWE-601 URL Redirection to Untrusted Site
References
-
github.com
/fardog/trailing-slash/commit/f8e66f1429308247e5a119d430203077d8f05048
web, patch, third-party-advisory
-
snyk.io
/vuln/SNYK-JS-TRAILINGSLASH-1085707
web, exploit, patch, third-party-advisory
-
github.com
/fardog/trailing-slash/blob/f640ece055fe85275c983de5eb94661b95e35670/index.js%23L36
web, broken-link
-
nvd.nist.gov
/vuln/detail/CVE-2021-23387
advisory
Sources
- CVE List CVE-2021-23387
- GitHub Advisory GHSA-rfhr-62xp-2fp2
- NVD CVE-2021-23387
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