OCaml 3.12.1 and earlier computes hash values without restricting the ability to trigger hash collisions predictably, which allows context-dependent attackers to cause a denial of service (CPU consumption) via crafted input to an application that maintains a hash table.

References

• https://nvd.nist.gov/vuln/detail/CVE-2012-0839
• http://openwall.com/lists/oss-security/2012/02/07/1
• http://openwall.com/lists/oss-security/2012/02/07/2
• http://secunia.com/advisories/47853
• http://www.mail-archive.com/caml-list@inria.fr/msg01477.html
• http://www.mail-archive.com/caml-list@inria.fr/msg01478.html
• http://www.nruns.com/_downloads/advisory28122011.pdf
• http://www.ocert.org/advisories/ocert-2011-003.html
• http://www.mail-archive.com/caml-list%40inria.fr/msg01477.html
• http://www.mail-archive.com/caml-list%40inria.fr/msg01478.html