Skip to content
Fencer Vulns
high 7.5

CVE-2009-1955 in the critical feed json

The expat XML parser in the apr_xml_* interface in xml/apr_xml.c in Apache APR-util before 1.3.7, as used in the mod_dav and mod_dav_svn mo…

published 2009-06-06 17 y ago modified 2026-06-16 4 mo ago also EUVD-2009-1950

cvss
7.5
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
53.0%
EPSS 53.0% chance of exploitation in 30 days, percentile 98%
public exploits
1
Exploit-DB

Summary

The expat XML parser in the apr_xml_* interface in xml/apr_xml.c in Apache APR-util before 1.3.7, as used in the mod_dav and mod_dav_svn modules in the Apache HTTP Server, allows remote attackers to cause a denial of service (memory consumption) via a crafted XML document containing a large number of nested entity references, as demonstrated by a PROPFIND request, a similar issue to CVE-2003-1564.

Patch / fix

  • apache apr-util 1.3.7
  • apache http_server 2.2.12
  • apple mac_os_x 10.6.2
  • apr-util Debian 14, Debian 13, Debian 12 1.3.7+dfsg-1

debian advisories DEBIAN-CVE-2009-1955

  • ant certificate system 7.3 1.6.5-1jpp_1rh
  • axis certificate system 7.3 1.2.1-1jpp_3rh
  • mx4j certificate system 7.3 1:3.0.1-1jpp_4rh
  • log4j certificate system 7.3 1.2.12-1jpp_1rh
  • tomcat5 certificate system 7.3 5.5.23-0jpp_4rh.16
  • rhpki-ca certificate system 7.3 7.3.0-20.el4
  • pcsc-lite certificate system 7.3 1.3.3-3.el4
  • rhpki-kra certificate system 7.3 7.3.0-14.el4

red hat advisories RHSA-2010:0602RHSA-2009:1160RHSA-2009:1108RHSA-2009:1107

  • apache2 openSUSE Tumbleweed 2.4.23-4.1

opensuse advisories openSUSE-SU-2024:10268-1

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2009-1955 updated cvss 5.0

apr-util billion laughs attack

  • Red Hat Certificate System 7.3 for 4AS ant 1.6.5-1jpp_1rh, axis 1.2.1-1jpp_3rh, mx4j 3.0.1-1jpp_4rh, log4j 1.2.12-1jpp_1rh, pcsc-lite 1.3.3-3.el4, rhpki-ca 7.3.0-20.el4, +31 more Red Hat Certificate System 7.3 for 4ES ant 1.6.5-1jpp_1rh, axis 1.2.1-1jpp_3rh, mx4j 3.0.1-1jpp_4rh, log4j 1.2.12-1jpp_1rh, pcsc-lite 1.3.3-3.el4, rhpki-ca 7.3.0-20.el4, +31 more
    fixed: vendor fix RHSA-2010:0602
  • Red Hat Desktop version 3 httpd 2.0.46-73.ent, mod_ssl 2.0.46-73.ent
    fixed: vendor fix RHSA-2009:1108
  • Red Hat Enterprise Linux (v. 5 server) apr-util 1.2.7-7.el5_3.1
    fixed: vendor fix RHSA-2009:1107
  • Red Hat Enterprise Linux AS version 3 httpd 2.0.46-73.ent, mod_ssl 2.0.46-73.ent
    fixed: vendor fix RHSA-2009:1108
  • Red Hat Enterprise Linux AS version 4 apr-util 0.9.4-22.el4_8.1 Red Hat Enterprise Linux Desktop (v. 5 client) apr-util 1.2.7-7.el5_3.1 Red Hat Enterprise Linux Desktop version 4 apr-util 0.9.4-22.el4_8.1 Red Hat Enterprise Linux Desktop Workstation (v. 5 client) apr-util 1.2.7-7.el5_3.1
    fixed: vendor fix RHSA-2009:1107
  • Red Hat Enterprise Linux ES version 3 httpd 2.0.46-73.ent, mod_ssl 2.0.46-73.ent
    fixed: vendor fix RHSA-2009:1108
  • Red Hat Enterprise Linux ES version 4 apr-util 0.9.4-22.el4_8.1
    fixed: vendor fix RHSA-2009:1107
  • Red Hat Enterprise Linux WS version 3 httpd 2.0.46-73.ent, mod_ssl 2.0.46-73.ent
    fixed: vendor fix RHSA-2009:1108
show 2 more
  • Red Hat Enterprise Linux WS version 4 apr-util 0.9.4-22.el4_8.1
    fixed: vendor fix RHSA-2009:1107
  • Red Hat JBoss Web Server 1.0 for RHEL 4 AS httpd22 2.2.10-23.1.ep5.el4, mod_ssl22 2.2.10-23.1.ep5.el4, httpd22-apr 2.2.10-23.1.ep5.el4, httpd22-apr-util 2.2.10-23.1.ep5.el4 Red Hat JBoss Web Server 1.0 for RHEL 4 ES httpd22 2.2.10-23.1.ep5.el4, mod_ssl22 2.2.10-23.1.ep5.el4, httpd22-apr 2.2.10-23.1.ep5.el4, httpd22-apr-util 2.2.10-23.1.ep5.el4
    fixed: vendor fix RHSA-2009:1160

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Timeline

  1. First public exploit (EDB-8842)
  2. Published

Exploit prediction

52.99% chance of exploitation in the next 30 days, higher than 98% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

  • EDB-8842 Apache mod_dav / svn - Remote Denial of Service dos, 2009-06-01

CVSS scores

assigned by version score vector
NVD 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD 2.0 5.0 AV:N/AC:L/Au:N/C:N/I:N/A:P

Classification

Weakness
  • CWE-776 Improper Restriction of Recursive Entity References in DTDs
Technology feeds

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.