CVE-2021-40509
CVE-2021-40509 is a medium-severity vulnerability in Jforum with a CVSS 3.x base score of 5.4. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-79.
Key facts
- Severity: Medium (CVSS 3.x base score 5.4)
- CVSS v2: 3.5
- EPSS exploit prediction: 1% (57th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-79
- Affected product: Jforum
- Published:
- Last modified:
Description
ViewCommon.java in JForum2 2.7.0 allows XSS via a user signature.
Frequently asked questions
- What is CVE-2021-40509?
- ViewCommon.java in JForum2 2.7.0 allows XSS via a user signature.
- How severe is CVE-2021-40509?
- CVE-2021-40509 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
- Is CVE-2021-40509 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (57th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-40509?
- CVE-2021-40509 affects Jforum. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2021-40509?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- When was CVE-2021-40509 published?
- CVE-2021-40509 was published on 2021-09-04 and last updated on 2026-06-17.
References
- http://packetstormsecurity.com/files/164045/jforum-2.7.0-Cross-Site-Scripting.html
- http://seclists.org/fulldisclosure/2021/Sep/13
- https://lists.openwall.net/full-disclosure/2021/09/03/7
- https://sourceforge.net/p/jforum2/code/934/
Affected products (1)
- cpe:2.3:a:jforum:jforum:2.7.0:*:*:*:*:*:*:*
More vulnerabilities in Jforum
- CVE-2022-26173 — High (CVSS 8.8): JForum v2.8.0 was discovered to contain a Cross-Site Request Forgery (CSRF) via…
- CVE-2013-7209 — Medium (CVSS 6.8): Cross-site request forgery (CSRF) vulnerability in admBase/login.page in the Admin module in JForum allows remote…
- CVE-2012-5338 — Medium (CVSS 5.8): Open redirect vulnerability in JForum 2.1.9 allows remote attackers to redirect users to arbitrary web sites and…
- CVE-2019-7550 — Medium (CVSS 5.3): In JForum 2.1.8, an unauthenticated, remote attacker can enumerate whether a user exists by using the "create user"…
- CVE-2012-5337 — Medium (CVSS 4.3): Multiple cross-site scripting (XSS) vulnerabilities in jforum.page in JForum 2.1.9 allow remote attackers to inject…
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