CVE-2020-18661 json
Cross Site Scripting (XSS) vulnerability in gnuboard5 <=v5.3.2.8 via the url parameter to bbs/login.php.
published 2021-06-24 5 y ago modified 2026-06-17 4 mo ago also EUVD-2020-10585
- cvss
- 6.1
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.1%
- EPSS 1.1% chance of exploitation in 30 days, percentile 66%
- public exploits
- 0
- none known
Summary
Cross Site Scripting (XSS) vulnerability in gnuboard5 <=v5.3.2.8 via the url parameter to bbs/login.php.
Exploit prediction
1.14% chance of exploitation in the next 30 days, higher than 66% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- github.com https://github.com/gnuboard/gnuboard5/issues/43 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| 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 | 4.3 | AV:N/AC:M/Au:N/C:N/I:P/A:N |
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
References
-
github.com
/gnuboard/gnuboard5/issues/43
exploit, third-party-advisory
-
seebug.org
/vuldb/ssvid-97925
third-party-advisory
-
github.com
/LoRexxar/CVE_Request/tree/master/gnuboard5%20mul%20vuls%20before%20v5.3.2.8#limited-reflective-xss-in-bbslogi
third-party-advisory
Sources
- CVE List CVE-2020-18661
- NVD CVE-2020-18661
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