Medium severity · published Oct 6, 2026
CVE-2026-105111
Apache Commons BCEL: Class2HTML emits unescaped class strings, enabling stored XSS
4.7
CVSS
0.2%
EPSS
No
On KEV
Description
Improper neutralization of input during web page generation ('cross-site scripting') vulnerability in Apache Commons BCEL.
This only happens when you're using Class2HTML to generate webpages for possibly-attacker-controlled class files, where Class2HTML emitters write attacker class-file strings into HTML unescaped (stored XSS in reports).
This issue affects Apache Commons BCEL: before 6.13.0.
Users are recommended to upgrade to version 6.13.0, which fixes the issue.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:L/A:N
Attack vector
Network
Complexity
High
Privileges
None
User interaction
Required
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 16% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
AC
Apache Commons BCEL · Apache Software Foundation
before 6.13.0; before fb72c225cbc6ec3d94060ed6edb269f07428d504 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-105111
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-105111
patch
https://github.com/apache/commons-bcel/commit/fb72c225cbc6ec3d94060ed6edb269f07428d504.patch
vendor-advisory
https://lists.apache.org/thread.html/co1wfk2lyrmpnfhn49o370pvfl978rw6
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