High 7.5Published Oct 9, 2026

CVE-2026-78384Apache CXF: Unbounded DEFLATE Decompression in CXF JOSE/JWE and SAML Processing (Decompression Bomb)

Updated under an hour ago (Oct 27, 2026, 8:50 AM ET)

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It affects Apache Software Foundation Apache CXF and 1 other product. Add what you run to find out whether that includes you.

EPSS puts the chance of exploitation in the next 30 days at 0.37%, higher than 30% of scored CVEs.

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Every CVE for Apache Software Foundation Apache CXF

Exploited in the last 30 days

CompressionUtils.inflate() decompressed attacker-controlled DEFLATE data with no output-size cap. A small (~KB) crafted payload could expand to gigabytes on the heap. Reachable via JWE decryption when zip=DEF (e.g. JoseSessionTokenProvider with RSA-OAEP key wrap) and via SAML redirect/POST binding token inflation — in both cases decompression happens before/independent of trust validation. Fix: Added a configurable maximum inflated-size cap (default 10 MiB, org.apache.cxf.compression-max-inflated-size system property) to CompressionUtils.inflate(); aborts with DataFormatException once exceeded. Users are recommended to upgrade to versions 4.2.4 or 4.1.9 or 3.6.13, which fix this issue.

CVSS: 7.5 HIGH (v3.1, CISA ADP)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Weakness (CWE): CWE-409
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): 0.37% (percentile 30)
Assigned by: apache
NVD analysis: Analyzed
Record last updated: Oct 15, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

Apache Software Foundation Apache CXF apache_software_foundation:apache_cxf (from the name)	from 4.2.0 before 4.2.4; from 4.0.0 before 4.1.9; before 3.6.13	CNA record
apache cxf apache:cxf	before 3.6.13; from 4.0.0 before 4.1.9; from 4.2.0 before 4.2.4	NVD

References

References

https://lists.apache.org/thread.html/xoh63rlxn0m9koft5j4jxrfd0hf81v3q	vendor-advisory, issue-tracking
http://www.openwall.com/lists/oss-security/2026/10/09/6	mailing-list, third-party-advisory

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.