CVE-2026-78384 PUBLISHED

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

Assigner: apache
Reserved: 24.08.2026 Published: 09.10.2026 Updated: 09.10.2026

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.

Product Status

Vendor Apache Software Foundation
Product Apache CXF
Versions Default: unaffected
  • affected from 4.2.0 to 4.2.4 (excl.)
  • affected from 4.0.0 to 4.1.9 (excl.)
  • affected from 0 to 3.6.13 (excl.)

Credits

  • Guanping Zhang reported this vulnerability. finder

References