libxml2 2.6.32 and earlier does not properly detect recursion during entity expansion in an attribute value, which allows context-dependent
libxml2 2.6.32 and earlier does not properly detect recursion during entity expansion in an attribute value, which allows context-dependent attackers to cause a denial of service (memory and CPU consumption) via a crafted XML document.
- Published
- Aug 27, 2008
- Updated
- Jun 16, 2026
- EPSS
- 2.5% · 84th percentile
- CWE
- CWE-776
Sign in to follow · You’ll be notified if a followed record enters KEV, gets an exploit or is updated.
Report tools
Action score
27
Monitor
Low priority for now.
- CVSS
- 26 / 40 · 6.5 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 1 / 30 · 2.5%
Affected systems
| Vendor | Product | CPE |
|---|---|---|
| xmlsoft | libxml2 | cpe:2.3:a:xmlsoft:libxml2 |
| apple | safari | cpe:2.3:a:apple:safari |
| apple | iphone os | cpe:2.3:o:apple:iphone_os |
| fedoraproject | fedora | cpe:2.3:o:fedoraproject:fedora |
| canonical | ubuntu linux | cpe:2.3:o:canonical:ubuntu_linux |
| debian | debian linux | cpe:2.3:o:debian:debian_linux |
| redhat | enterprise linux desktop | cpe:2.3:o:redhat:enterprise_linux_desktop |
| redhat | enterprise linux eus | cpe:2.3:o:redhat:enterprise_linux_eus |
| redhat | enterprise linux server | cpe:2.3:o:redhat:enterprise_linux_server |
| redhat | enterprise linux workstation | cpe:2.3:o:redhat:enterprise_linux_workstation |
| vmware | esx | cpe:2.3:o:vmware:esx |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- apple iphone os1.0.0 and later · before 3.0
- apple safaribefore 4.0
- canonical ubuntu linux6.06
- canonical ubuntu linux7.04
- canonical ubuntu linux7.10
- canonical ubuntu linux8.04
- debian debian linux4.0
- fedoraproject fedora9
- redhat enterprise linux desktop3.0
- redhat enterprise linux desktop4.0
- redhat enterprise linux desktop5.0
- redhat enterprise linux eus4.7
- redhat enterprise linux eus5.2
- redhat enterprise linux server2.0
- redhat enterprise linux server3.0
- redhat enterprise linux server4.0
- redhat enterprise linux server5.0
- redhat enterprise linux workstation2.0
- redhat enterprise linux workstation3.0
- redhat enterprise linux workstation4.0
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 2.6.32.dfsg-3 | 2.6.32.dfsg-3 |
| Debian:4.0 | libxml2 | before 2.6.27.dfsg-3 | 2.6.27.dfsg-3 |
| Debian:5.0 | libxml2 | before 2.6.32.dfsg-2+lenny1 | 2.6.32.dfsg-2+lenny1 |
| Red Hat:enterprise_linux:2.1::as | libxml2 | before 0:2.4.19-9.ent | 0:2.4.19-9.ent |
| Red Hat:enterprise_linux:2.1::as | libxml2-devel | before 0:2.4.19-9.ent | 0:2.4.19-9.ent |
| Red Hat:enterprise_linux:2.1::as | libxml2-python | before 0:2.4.19-9.ent | 0:2.4.19-9.ent |
| Red Hat:enterprise_linux:3::as | libxml2 | before 0:2.5.10-11 | 0:2.5.10-11 |
| Red Hat:enterprise_linux:3::as | libxml2-debuginfo | before 0:2.5.10-11 | 0:2.5.10-11 |
| Red Hat:enterprise_linux:3::as | libxml2-devel | before 0:2.5.10-11 | 0:2.5.10-11 |
| Red Hat:enterprise_linux:3::as | libxml2-python | before 0:2.5.10-11 | 0:2.5.10-11 |
| Red Hat:enterprise_linux:4::as | libxml2 | before 0:2.6.16-12.3 | 0:2.6.16-12.3 |
| Red Hat:enterprise_linux:4::as | libxml2-debuginfo | before 0:2.6.16-12.3 | 0:2.6.16-12.3 |
| Red Hat:enterprise_linux:4::as | libxml2-devel | before 0:2.6.16-12.3 | 0:2.6.16-12.3 |
| Red Hat:enterprise_linux:4::as | libxml2-python | before 0:2.6.16-12.3 | 0:2.6.16-12.3 |
| Red Hat:enterprise_linux:5::client | libxml2-python | before 0:2.6.26-2.1.2.4 | 0:2.6.26-2.1.2.4 |
| Red Hat:enterprise_linux:5::client_workstation | libxml2 | before 0:2.6.26-2.1.2.4 | 0:2.6.26-2.1.2.4 |
| Red Hat:enterprise_linux:5::client_workstation | libxml2-debuginfo | before 0:2.6.26-2.1.2.4 | 0:2.6.26-2.1.2.4 |
| Red Hat:enterprise_linux:5::client_workstation | libxml2-devel | before 0:2.6.26-2.1.2.4 | 0:2.6.26-2.1.2.4 |
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 | 2.6.32.dfsg-3 · Debian:12 | Package registry (OSV) |
| red hat:libxml2 | 0:2.4.19-9.ent · Red Hat:enterprise_linux:2.1::as | Package registry (OSV) |
| red hat:libxml2-debuginfo | 0:2.5.10-11 · Red Hat:enterprise_linux:3::as | Package registry (OSV) |
| red hat:libxml2-devel | 0:2.4.19-9.ent · Red Hat:enterprise_linux:2.1::as | Package registry (OSV) |
| red hat:libxml2-python | 0:2.4.19-9.ent · Red Hat:enterprise_linux:2.1::as | 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
- Anyone who can reach it over the internet can trigger it.
- No account or password is required.
- A user must open a link or visit a page.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- none
- Integrity
- none
- Availability
- high · the service can be disrupted
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- Required
- Scope
- Unchanged
- Confidentiality impact
- None
- Integrity impact
- None
- Availability impact
- High
Weakness class (CWE)
CWE-776 · Improper Restriction of Recursive Entity References in DTDs ('XML Entity Expansion')CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
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.
Attack patterns (CAPEC)
ATT&CK techniques
—
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✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
- secunia.com/advisories/31748
- lists.apple.com/archives/security-announce/2009/Jun/msg00005.html
- lists.apple.com/archives/security-announce/2009/jun/msg00002.html
- lists.opensuse.org/opensuse-security-announce/2008-09/msg00004.html
- lists.vmware.com/pipermail/security-announce/2008/000039.html
- mail.gnome.org/archives/xml/2008-August/msg00034.html
- secunia.com/advisories/31558
- secunia.com/advisories/31566
- secunia.com/advisories/31590
- secunia.com/advisories/31728
- secunia.com/advisories/31855
- secunia.com/advisories/31982
- secunia.com/advisories/32488
- secunia.com/advisories/32807
- secunia.com/advisories/32974
- secunia.com/advisories/35379
- security.gentoo.org/glsa/glsa-200812-06.xml
- support.apple.com/kb/HT3613
- support.apple.com/kb/HT3639
- svn.gnome.org/viewvc/libxml2?view=revision&revision=3772
Vendor advisories and official records. Exploit/PoC links are deliberately left out.