CVE-2021-23937 json
DNS proxy and possible amplification attack
published 5y ago modified 4mo ago also GHSA-hmhg-95wh-r699 , EUVD-2022-4175
- cvss
- 7.5
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 4.3%
- EPSS 4.3% chance of exploitation in 30 days, percentile 91%
- public exploits
- 0
- none known
Summary
A DNS proxy and possible amplification attack vulnerability in WebClientInfo of Apache Wicket allows an attacker to trigger arbitrary DNS lookups from the server when the X-Forwarded-For header is not properly sanitized. This DNS lookup can be engineered to overload an internal DNS server or to slow down request processing of the Apache Wicket application causing a possible denial of service on either the internal infrastructure or the web application itself. This issue affects Apache Wicket Apache Wicket 9.x version 9.2.0 and prior versions; Apache Wicket 8.x version 8.11.0 and prior versions; Apache Wicket 7.x version 7.17.0 and prior versions and Apache Wicket 6.x version 6.2.0 and later versions.
Patch / fix
Is CVE-2021-23937 in your dependencies? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerExploit prediction
4.26% chance of exploitation in the next 30 days, higher than 91% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| NVD | 2.0 | 5.0 | AV:N/AC:L/Au:N/C:N/I:N/A:P |
| GitHub | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| maven | org.apache.wicket:wicket-core | >=9.0.0, <9.3.0 >=8.0.0, <8.12.0 <7.18.0 |
9.3.0 8.12.0 7.18.0 |
Affected products
- Apache Software Foundation Apache Wicket
Classification
References
-
github.com
/apache/wicket/commit/84f62a5cff462eaa3bfaf171b0638c7e7feea30d
web
-
lists.apache.org
/thread.html/rc2ef22f90793e158cef65a7e370cdbca023c499d1403d65feeca870d%40%3Cusers.wicket.apache.org%3E
web, mailing-list, release-notes, vendor-advisory
-
lists.apache.org
/thread.html/r127c0c1f3cb71e5bc619ad1e4b898b97c49758d1f20a54042966473e%40%3Cannounce.wicket.apache.org%3E
mailing-list
-
lists.apache.org
/thread.html/r127c0c1f3cb71e5bc619ad1e4b898b97c49758d1f20a54042966473e%40%3Cusers.wicket.apache.org%3E
mailing-list
-
lists.apache.org
/thread.html/r8ccbd91b56ebf045d151bd4282bfeea7842a0698a0b76118fca8fe78%40%3Cdev.wicket.apache.org%3E
mailing-list
-
nvd.nist.gov
/vuln/detail/CVE-2021-23937
advisory
-
github.com
/apache/wicket
package
-
lists.apache.org
/thread.html/r127c0c1f3cb71e5bc619ad1e4b898b97c49758d1f20a54042966473e@%3Cannounce.wicket.apache.org%3E
web
-
lists.apache.org
/thread.html/r127c0c1f3cb71e5bc619ad1e4b898b97c49758d1f20a54042966473e@%3Cusers.wicket.apache.org%3E
web
-
lists.apache.org
/thread.html/r8ccbd91b56ebf045d151bd4282bfeea7842a0698a0b76118fca8fe78@%3Cdev.wicket.apache.org%3E
web
-
lists.apache.org
/thread.html/rc2ef22f90793e158cef65a7e370cdbca023c499d1403d65feeca870d@%3Cusers.wicket.apache.org%3E
web
-
lists.apache.org
/thread.html/rce158bb896c9ef812393a11646fdef7b9023833e54854c4302ff7b70@%3Cdev.wicket.apache.org%3E
web
-
lists.apache.org
/thread.html/rce23bba1e11368f9f4cccce0e9b02b88dcdac4e4b2304e66bd098cf5@%3Cannounce.wicket.apache.org%3E
web
-
openwall.com
/lists/oss-security/2021/05/25/2
web
Sources
- CVE List CVE-2021-23937
- GitHub Advisory GHSA-hmhg-95wh-r699
- NVD CVE-2021-23937
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.