Description
expat_erl.c in ejabberd before 2.1.7 and 3.x before 3.0.0-alpha-3, and exmpp before 0.9.7, does not properly detect recursion during entity expansion, which allows remote attackers to cause a denial of service (memory and CPU consumption) via a crafted XML document containing a large number of nested entity references, a similar issue to CVE-2003-1564.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | ejabberd | 2.1.6-2.1 | — |
| Debian 13 | ejabberd | 2.1.6-2.1 | — |
| Debian 12 | ejabberd | 2.1.6-2.1 | — |
| Debian 6.0 | ejabberd | 2.1.5-3+squeeze1 | DSA-2248-1 |
| Debian 5.0 | ejabberd | 2.0.1-6+lenny3 | DSA-2248-1 |
Advisories 1
- DSA-2248-1 ejabberd - denial of service Debian Security (DSA / DLA) · Mar 9, 2026
References
- ejabberd-xml-dos(67769) vdb-entry
- DSA-2248 vendor-advisory
- http://www.process-one.net/en/ejabberd/release_notes/release_note_ejabberd_2.1.7/
- 44765 third-party-advisory
- https://git.process-one.net/ejabberd/mainline/commit/bd1df027c622e1f96f9eeaac612a6a956c1ff0b6
- FEDORA-2011-8415 vendor-advisory
- http://www.ejabberd.im/ejabberd-2.1.7
- https://bugzilla.redhat.com/show_bug.cgi?id=700454
- 44807 third-party-advisory
- 48072 vdb-entry
- FEDORA-2011-8437 vendor-advisory
- 45120 third-party-advisory