Memory leak in the poolGrow function in expat/lib/xmlparse.c in expat before 2.1.0 allows context-dependent attackers to cause a denial of s
Memory leak in the poolGrow function in expat/lib/xmlparse.c in expat before 2.1.0 allows context-dependent attackers to cause a denial of service (memory consumption) via a large number of crafted XML files that cause improperly-handled reallocation failures when expanding entities.
- Published
- Jul 3, 2012
- Updated
- Jun 16, 2026
- EPSS
- 3.6% · 89th percentile
- CWE
- CWE-399
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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 · 3.6%
Affected systems
| Vendor | Product | CPE |
|---|---|---|
| libexpat project | libexpat | cpe:2.3:a:libexpat_project:libexpat |
| apple | mac os x | cpe:2.3:o:apple:mac_os_x |
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 10.11.1 inclusive
- libexpat project libexpatup to 2.0.1 inclusive
- libexpat project libexpat1.95.1
- libexpat project libexpat1.95.2
- libexpat project libexpat1.95.4
- libexpat project libexpat1.95.5
- libexpat project libexpat1.95.6
- libexpat project libexpat1.95.7
- libexpat project libexpat1.95.8
- libexpat project libexpat2.0.0
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| Debian:12 | expat | before 2.1.0~beta3-1 | 2.1.0~beta3-1 |
| Debian:12 | libxmltok | all versions | — |
| Debian:12 | xmlrpc-c | before 1.16.33-3.2 | 1.16.33-3.2 |
| Debian:6.0 | expat | before 2.0.1-7+squeeze1 | 2.0.1-7+squeeze1 |
| openSUSE:Tumbleweed | expat | before 2.2.0-3.1 | 2.2.0-3.1 |
| Red Hat:enterprise_linux:5::client | expat | before 0:1.95.8-11.el5_8 | 0:1.95.8-11.el5_8 |
| Red Hat:enterprise_linux:5::client | expat-debuginfo | before 0:1.95.8-11.el5_8 | 0:1.95.8-11.el5_8 |
| Red Hat:enterprise_linux:5::client_workstation | expat-devel | before 0:1.95.8-11.el5_8 | 0:1.95.8-11.el5_8 |
| Red Hat:enterprise_linux:6::client | expat | before 0:2.0.1-11.el6_2 | 0:2.0.1-11.el6_2 |
| Red Hat:enterprise_linux:6::client | expat-debuginfo | before 0:2.0.1-11.el6_2 | 0:2.0.1-11.el6_2 |
| Red Hat:enterprise_linux:6::client | expat-devel | before 0:2.0.1-11.el6_2 | 0:2.0.1-11.el6_2 |
Same product
libexpat project: all recordsOther highest-scoring records for the same primary product.
- CVE-2022-25236xmlparse.c in Expat (aka libexpat) before 2.4.5 allows attackers to insert namespace-separator characters into namespace URIs.50Plan
- CVE-2022-25315In Expat (aka libexpat) before 2.4.5, there is an integer overflow in storeRawNames.40Plan
- CVE-2022-25235xmltok_impl.c in Expat (aka libexpat) before 2.4.5 lacks certain validation of encoding, such as checks for whether a UTF-8 character is val40Plan
- CVE-2022-23852Expat (aka libexpat) before 2.4.4 has a signed integer overflow in XML_GetBuffer, for configurations with a nonzero XML_CONTEXT_BYTES.40Plan
- CVE-2022-22824defineAttribute in xmlparse.c in Expat (aka libexpat) before 2.4.3 has an integer overflow.40Plan
- CVE-2022-22823build_model in xmlparse.c in Expat (aka libexpat) before 2.4.3 has an integer overflow.40Plan
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:expat | 2.1.0~beta3-1 · Debian:12 | Package registry (OSV) |
| debian:xmlrpc-c | 1.16.33-3.2 · Debian:12 | Package registry (OSV) |
| opensuse:expat | 2.2.0-3.1 · openSUSE:Tumbleweed | Package registry (OSV) |
| red hat:expat | 0:1.95.8-11.el5_8 · Red Hat:enterprise_linux:5::client | Package registry (OSV) |
| red hat:expat-debuginfo | 0:1.95.8-11.el5_8 · Red Hat:enterprise_linux:5::client | Package registry (OSV) |
| red hat:expat-devel | 0:1.95.8-11.el5_8 · Red Hat:enterprise_linux:5::client_workstation | 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)
CWE-399 · Resource Management ErrorsCVSS 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
- expat.cvs.sourceforge.net/viewvc/expat/expat/lib/xmlparse.c?r1=1.166&r2=1.167
- lists.apple.com/archives/security-announce/2015/Dec/msg00005.html
- rhn.redhat.com/errata/RHSA-2012-0731.html
- rhn.redhat.com/errata/RHSA-2016-0062.html
- rhn.redhat.com/errata/RHSA-2016-2957.html
- secunia.com/advisories/49504
- secunia.com/advisories/51024
- secunia.com/advisories/51040
- sourceforge.net/projects/expat/files/expat/2.1.0/
- sourceforge.net/tracker/?func=detail&atid=110127&aid=2958794&group_id=10127
- www.debian.org/security/2012/dsa-2525
- www.mandriva.com/security/advisories?name=MDVSA-2012:041
- www.securityfocus.com/bid/52379
- www.securitytracker.com/id/1034344
- www.ubuntu.com/usn/USN-1527-1
- www.ubuntu.com/usn/USN-1613-1
- www.ubuntu.com/usn/USN-1613-2
- support.apple.com/HT205637
Vendor advisories and official records. Exploit/PoC links are deliberately left out.