CVE-2026-107937 (GCVE-0-2026-107937)

Vulnerability from cvelistv5 – Published: 2026-10-09 10:19 – Updated: 2026-10-09 11:07
VLAI
Title
Apache CXF: The attachment header size and count limits can be bypassed, which allows denial of service through memory exhaustion.
Summary
In Apache CXF, the parser for multipart/MTOM attachment part headers did not fully enforce the configured attachment-max-header-size (default 300 characters) and attachment-headers-max-count (default 500) limits. The size limit was applied only to each physical line, not to a header value built from continuation lines or to the combined values of a repeated header. The count limit was checked against the number of distinct header names, not the total number of header lines. A remote, unauthenticated attacker could send a multipart request with very large folded or repeated part headers. The server would then allocate memory without bound, causing a denial of service.  Users are recommended to upgrade to versions 4.2.4 or 4.1.9 or 3.6.13, which fix this issue.
Severity
No CVSS data available.
Assigner
apache CNA under the mitre root
CNA scorecard B 76/100 over 939 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Apache Software Foundation Apache CXF Affected: 4.2.0 , < 4.2.4 (semver)
Affected: 4.0.0 , < 4.1.9 (semver)
Affected: 0 , < 3.6.13 (semver)
guessed Create a notification for this product.
Credits
This issue was found using Claude agents to study the security of open-source projects and independently by Mike Read (github.com/Michael-JRead)
Show details on NVD website
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