parser.c in libxml2 before 2.9.2 does not properly prevent entity expansion even when entity substitution has been disabled, which allows co
parser.c in libxml2 before 2.9.2 does not properly prevent entity expansion even when entity substitution has been disabled, which allows context-dependent attackers to cause a denial of service (CPU consumption) via a crafted XML document containing a large number of nested entity references, a variant of the "billion laughs" attack.
- Published
- Nov 4, 2014
- Updated
- Jun 16, 2026
- EPSS
- 4.0% · 90th percentile
- CWE
- —
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Report tools
Action score
21
Monitor
Low priority for now.
- CVSS
- 20 / 40 · 5.0 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 1 / 30 · 4.0%
Affected systems
| Vendor | Product | CPE |
|---|---|---|
| xmlsoft | libxml2 | cpe:2.3:a:xmlsoft:libxml2 |
| apple | mac os x | cpe:2.3:o:apple:mac_os_x |
| canonical | ubuntu linux | cpe:2.3:o:canonical:ubuntu_linux |
| debian | debian linux | cpe:2.3:o:debian:debian_linux |
| redhat | enterprise linux | cpe:2.3:o:redhat:enterprise_linux |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- apple mac os xup to 10.10.4 inclusive
- canonical ubuntu linux10.04
- canonical ubuntu linux12.04
- canonical ubuntu linux14.04
- debian debian linux7.0
- redhat enterprise linux5.0
- xmlsoft libxml2up to 2.9.1 inclusive
- xmlsoft libxml22.0.0
- xmlsoft libxml22.1.0
- xmlsoft libxml22.1.1
- xmlsoft libxml22.2.0
- xmlsoft libxml22.2.1
- xmlsoft libxml22.2.10
- xmlsoft libxml22.2.11
- xmlsoft libxml22.2.2
- xmlsoft libxml22.2.3
- xmlsoft libxml22.2.4
- xmlsoft libxml22.2.5
- xmlsoft libxml22.2.6
- xmlsoft libxml22.2.7
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| Debian:12 | libxml2 | before 2.9.2+dfsg1-1 | 2.9.2+dfsg1-1 |
| Debian:6.0 | libxml2 | before 2.7.8.dfsg-2+squeeze11 | 2.7.8.dfsg-2+squeeze11 |
| Debian:6.0 | libxml2 | before 2.7.8.dfsg-2+squeeze10 | 2.7.8.dfsg-2+squeeze10 |
| Debian:7 | libxml2 | before 2.8.0+dfsg1-7+wheezy3 | 2.8.0+dfsg1-7+wheezy3 |
| Debian:7 | libxml2 | before 2.8.0+dfsg1-7+wheezy2 | 2.8.0+dfsg1-7+wheezy2 |
| openSUSE:Tumbleweed | libxml2 | before 2.9.4-1.22 | 2.9.4-1.22 |
| Red Hat:enterprise_linux:5::client | libxml2 | before 0:2.6.26-2.1.25.el5_11 | 0:2.6.26-2.1.25.el5_11 |
| Red Hat:enterprise_linux:5::client | libxml2-debuginfo | before 0:2.6.26-2.1.25.el5_11 | 0:2.6.26-2.1.25.el5_11 |
| Red Hat:enterprise_linux:5::client | libxml2-python | before 0:2.6.26-2.1.25.el5_11 | 0:2.6.26-2.1.25.el5_11 |
| Red Hat:enterprise_linux:5::client_workstation | libxml2-devel | before 0:2.6.26-2.1.25.el5_11 | 0:2.6.26-2.1.25.el5_11 |
| Red Hat:enterprise_linux:6::client | libxml2 | before 0:2.7.6-17.el6_6.1 | 0:2.7.6-17.el6_6.1 |
| Red Hat:enterprise_linux:6::client | libxml2-debuginfo | before 0:2.7.6-17.el6_6.1 | 0:2.7.6-17.el6_6.1 |
| Red Hat:enterprise_linux:6::client | libxml2-devel | before 0:2.7.6-17.el6_6.1 | 0:2.7.6-17.el6_6.1 |
| Red Hat:enterprise_linux:6::client | libxml2-python | before 0:2.7.6-17.el6_6.1 | 0:2.7.6-17.el6_6.1 |
| Red Hat:enterprise_linux:6::client | libxml2-static | before 0:2.7.6-17.el6_6.1 | 0:2.7.6-17.el6_6.1 |
| Red Hat:enterprise_linux:7::client | libxml2 | before 0:2.9.1-5.el7_0.1 | 0:2.9.1-5.el7_0.1 |
| Red Hat:enterprise_linux:7::client | libxml2-debuginfo | before 0:2.9.1-5.el7_0.1 | 0:2.9.1-5.el7_0.1 |
| Red Hat:enterprise_linux:7::client | libxml2-devel | before 0:2.9.1-5.el7_0.1 | 0:2.9.1-5.el7_0.1 |
| Red Hat:enterprise_linux:7::client | libxml2-python | before 0:2.9.1-5.el7_0.1 | 0:2.9.1-5.el7_0.1 |
| Red Hat:enterprise_linux:7::client | libxml2-static | before 0:2.9.1-5.el7_0.1 | 0:2.9.1-5.el7_0.1 |
Same product
xmlsoft: all recordsOther highest-scoring records for the same primary product.
- CVE-2008-3529Heap-based buffer overflow in the xmlParseAttValueComplex function in parser.c in libxml2 before 2.7.0 allows context-dependent attackers to47Plan
- CVE-2017-7376Buffer overflow in libxml2 allows remote attackers to execute arbitrary code by leveraging an incorrect limit for port values when handling 46Plan
- CVE-2022-40303An issue was discovered in libxml2 before 2.10.3.42Plan
- CVE-2021-3518There's a flaw in libxml2 in versions before 2.9.11.42Plan
- CVE-2011-1944Integer overflow in xpath.c in libxml2 2.6.x through 2.6.32 and 2.7.x through 2.7.8, and libxml 1.8.16 and earlier, allows context-dependent41Plan
- CVE-2017-7375A flaw in libxml2 allows remote XML entity inclusion with default parser flags (i.e., when the caller did not request entity substitution, D40Plan
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| debian:libxml2 | 2.9.2+dfsg1-1 · Debian:12 | Package registry (OSV) |
| opensuse:libxml2 | 2.9.4-1.22 · openSUSE:Tumbleweed | Package registry (OSV) |
| red hat:libxml2 | 0:2.7.6-17.el6_6.1 · Red Hat:enterprise_linux:6::client | Package registry (OSV) |
| red hat:libxml2-debuginfo | 0:2.7.6-17.el6_6.1 · Red Hat:enterprise_linux:6::client | Package registry (OSV) |
| red hat:libxml2-devel | 0:2.7.6-17.el6_6.1 · Red Hat:enterprise_linux:6::client | Package registry (OSV) |
| red hat:libxml2-python | 0:2.7.6-17.el6_6.1 · Red Hat:enterprise_linux:6::client | Package registry (OSV) |
| red hat:libxml2-static | 0:2.7.6-17.el6_6.1 · Red Hat:enterprise_linux:6::client | Package registry (OSV) |
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
No commit or PR link among the references.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
No nightly-computed relations.
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
Attack conditions
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- none
- Integrity
- none
- Availability
- P · the service can be disrupted
- Attack complexity
- Low
- Confidentiality impact
- None
- Integrity impact
- None
- Availability impact
- P
Weakness class (CWE)
—
CVSS vector
AV:N/AC:L/Au:N/C:N/I:N/A:P
nvd-primary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
MITRE has no CAPEC/ATT&CK mapping for this CWE.
Noroxi analysis
No Noroxi analysis for this record yet
We don't hand-write analysis for all 385,000+ vulnerabilities; that wouldn't be honest. For notable, high-impact vulnerabilities our team writes the mechanism, detection and remediation steps.
We use this product, ask for helpChange log
- Fix✗ → ✓
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References
- kb.juniper.net/InfoCenter/index?page=content&id=JSA10705
- lists.apple.com/archives/security-announce/2015/Aug/msg00001.html
- lists.apple.com/archives/security-announce/2015/Aug/msg00002.html
- lists.opensuse.org/opensuse-updates/2014-10/msg00034.html
- lists.opensuse.org/opensuse-updates/2015-12/msg00120.html
- rhn.redhat.com/errata/RHSA-2014-1655.html
- rhn.redhat.com/errata/RHSA-2014-1885.html
- secunia.com/advisories/59903
- secunia.com/advisories/61965
- secunia.com/advisories/61966
- secunia.com/advisories/61991
- www.debian.org/security/2014/dsa-3057
- www.mandriva.com/security/advisories?name=MDVSA-2014:244
- www.openwall.com/lists/oss-security/2014/10/17/7
- www.oracle.com/technetwork/topics/security/bulletinjan2015-2370101.html
- www.oracle.com/technetwork/topics/security/ovmbulletinjul2016-3090546.html
- www.securityfocus.com/bid/70644
- www.ubuntu.com/usn/USN-2389-1
- bugzilla.redhat.com/attachment.cgi?id=944444&action=diff
- bugzilla.redhat.com/show_bug.cgi?id=1149084
Vendor advisories and official records. Exploit/PoC links are deliberately left out.