Heap-based buffer overflow in the xmlFAParsePosCharGroup function in libxml2 before 2.9.4, as used in Apple iOS before 9.3.2, OS X before 10
Heap-based buffer overflow in the xmlFAParsePosCharGroup function in libxml2 before 2.9.4, as used in Apple iOS before 9.3.2, OS X before 10.11.5, tvOS before 9.2.1, and watchOS before 2.2.1, allows remote attackers to execute arbitrary code or cause a denial of service (memory corruption) via a crafted XML document.
- Published
- May 20, 2016
- Updated
- Jun 16, 2026
- EPSS
- 3.2% · 88th percentile
- CWE
- CWE-119
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Report tools
Action score
32
Monitor
Low priority for now.
- CVSS
- 31 / 40 · 7.8 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 1 / 30 · 3.2%
Affected systems
| Vendor | Product | CPE |
|---|---|---|
| apple | iphone os | cpe:2.3:o:apple:iphone_os |
| apple | mac os x | cpe:2.3:o:apple:mac_os_x |
| apple | tvos | cpe:2.3:o:apple:tvos |
| apple | watchos | cpe:2.3:o:apple:watchos |
| debian | debian linux | cpe:2.3:o:debian:debian_linux |
| canonical | ubuntu linux | cpe:2.3:o:canonical:ubuntu_linux |
| redhat | enterprise linux desktop | cpe:2.3:o:redhat:enterprise_linux_desktop |
| redhat | enterprise linux server | cpe:2.3:o:redhat:enterprise_linux_server |
| redhat | enterprise linux server aus | cpe:2.3:o:redhat:enterprise_linux_server_aus |
| redhat | enterprise linux server eus | cpe:2.3:o:redhat:enterprise_linux_server_eus |
| redhat | enterprise linux server tus | cpe:2.3:o:redhat:enterprise_linux_server_tus |
| redhat | enterprise linux workstation | cpe:2.3:o:redhat:enterprise_linux_workstation |
and 2 more
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- apple iphone osbefore 9.3.2
- apple mac os xbefore 10.11.5
- apple tvosbefore 9.2.1
- apple watchosbefore 2.2.1
- canonical ubuntu linux12.04
- canonical ubuntu linux14.04
- canonical ubuntu linux15.10
- canonical ubuntu linux16.04
- debian debian linux8.0
- mcafee web gateway7.6.0.0 and later · up to 7.6.2.3 inclusive
- mcafee web gateway7.5.0.0 and later · up to 7.5.2.10 inclusive
- redhat enterprise linux desktop6.0
- redhat enterprise linux desktop7.0
- redhat enterprise linux server6.0
- redhat enterprise linux server7.0
- redhat enterprise linux server aus7.2
- redhat enterprise linux server aus7.3
- redhat enterprise linux server aus7.4
- redhat enterprise linux server aus7.6
- redhat enterprise linux server eus7.2
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 2.9.3+dfsg1-1.1 | 2.9.3+dfsg1-1.1 |
| Debian:7 | libxml2 | before 2.8.0+dfsg1-7+wheezy6 | 2.8.0+dfsg1-7+wheezy6 |
| Debian:8 | libxml2 | before 2.9.1+dfsg1-5+deb8u2 | 2.9.1+dfsg1-5+deb8u2 |
| openSUSE:Tumbleweed | python-libxml2 | before 2.9.4-1.4 | 2.9.4-1.4 |
| Red Hat:enterprise_linux:6::client | libxml2 | before 0:2.7.6-21.el6_8.1 | 0:2.7.6-21.el6_8.1 |
| Red Hat:enterprise_linux:6::client | libxml2-debuginfo | before 0:2.7.6-21.el6_8.1 | 0:2.7.6-21.el6_8.1 |
| Red Hat:enterprise_linux:6::client | libxml2-devel | before 0:2.7.6-21.el6_8.1 | 0:2.7.6-21.el6_8.1 |
| Red Hat:enterprise_linux:6::client | libxml2-python | before 0:2.7.6-21.el6_8.1 | 0:2.7.6-21.el6_8.1 |
| Red Hat:enterprise_linux:6::client | libxml2-static | before 0:2.7.6-21.el6_8.1 | 0:2.7.6-21.el6_8.1 |
| Red Hat:enterprise_linux:7::client | libxml2 | before 0:2.9.1-6.el7_2.3 | 0:2.9.1-6.el7_2.3 |
| Red Hat:enterprise_linux:7::client | libxml2-debuginfo | before 0:2.9.1-6.el7_2.3 | 0:2.9.1-6.el7_2.3 |
| Red Hat:enterprise_linux:7::client | libxml2-devel | before 0:2.9.1-6.el7_2.3 | 0:2.9.1-6.el7_2.3 |
| Red Hat:enterprise_linux:7::client | libxml2-python | before 0:2.9.1-6.el7_2.3 | 0:2.9.1-6.el7_2.3 |
| Red Hat:enterprise_linux:7::client | libxml2-static | before 0:2.9.1-6.el7_2.3 | 0:2.9.1-6.el7_2.3 |
| SUSE:Linux Enterprise Desktop 12 | libxml2 | before 2.9.1-24.1 | 2.9.1-24.1 |
| SUSE:Linux Enterprise Desktop 12 | python-libxml2 | before 2.9.1-24.1 | 2.9.1-24.1 |
| SUSE:Linux Enterprise Software Development Kit 11 SP4 | libxml2 | before 2.7.6-0.44.1 | 2.7.6-0.44.1 |
| SUSE:OpenStack Cloud 5 | libxml2-python | before 2.7.6-0.44.4 | 2.7.6-0.44.4 |
Same product
apple: all recordsOther highest-scoring records for the same primary product.
- CVE-2016-4657WebKit in Apple iOS before 9.3.5 allows remote attackers to execute arbitrary code or cause a denial of service (memory corruption) via a crKEV85Now
- CVE-2014-4404Heap-based buffer overflow in IOHIDFamily in Apple iOS before 8 and Apple TV before 7 allows attackers to execute arbitrary code in a privilKEV76This week
- CVE-2021-30762A use after free issue was addressed with improved memory management.KEV68This week
- CVE-2021-30761A memory corruption issue was addressed with improved state management.KEV68This week
- CVE-2016-4656The kernel in Apple iOS before 9.3.5 allows attackers to execute arbitrary code in a privileged context or cause a denial of service (memoryKEV68This week
- CVE-2021-30666A buffer overflow issue was addressed with improved memory handling.KEV66This week
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 | 2.9.3+dfsg1-1.1 · Debian:12 | Package registry (OSV) |
| opensuse:python-libxml2 | 2.9.4-1.4 · openSUSE:Tumbleweed | Package registry (OSV) |
| red hat:libxml2 | 0:2.7.6-21.el6_8.1 · Red Hat:enterprise_linux:6::client | Package registry (OSV) |
| red hat:libxml2-debuginfo | 0:2.7.6-21.el6_8.1 · Red Hat:enterprise_linux:6::client | Package registry (OSV) |
| red hat:libxml2-devel | 0:2.7.6-21.el6_8.1 · Red Hat:enterprise_linux:6::client | Package registry (OSV) |
| red hat:libxml2-python | 0:2.7.6-21.el6_8.1 · Red Hat:enterprise_linux:6::client | Package registry (OSV) |
| red hat:libxml2-static | 0:2.7.6-21.el6_8.1 · Red Hat:enterprise_linux:6::client | Package registry (OSV) |
| suse:libxml2 | 2.9.1-24.1 · SUSE:Linux Enterprise Desktop 12 | Package registry (OSV) |
| suse:libxml2-python | 2.7.6-0.44.4 · SUSE:OpenStack Cloud 5 | Package registry (OSV) |
| suse:python-libxml2 | 2.9.1-24.1 · SUSE:Linux Enterprise Desktop 12 | 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.
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
- Someone with local access to the system 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
- high · data can be read
- Integrity
- high · data or configuration can be modified
- Availability
- high · the service can be disrupted
- Attack vector
- Local
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- Required
- Scope
- Unchanged
- Confidentiality impact
- High
- Integrity impact
- High
- Availability impact
- High
Weakness class (CWE)
CWE-119 · Improper Restriction of Operations within the Bounds of a Memory BufferCVSS vector
CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/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)
- Buffer Overflow via Environment VariablesCAPEC-10likelihood: High · High
- Overflow BuffersCAPEC-100likelihood: High · Very High
- Buffer ManipulationCAPEC-123likelihood: High · Very High
- Client-side Injection-induced Buffer OverflowCAPEC-14likelihood: Medium · High
- Filter Failure through Buffer OverflowCAPEC-24likelihood: High · High
- MIME ConversionCAPEC-42likelihood: High · High
- Overflow Binary Resource FileCAPEC-44likelihood: High · Very High
- Buffer Overflow via Symbolic LinksCAPEC-45likelihood: High · High
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
- lists.apple.com/archives/security-announce/2016/May/msg00001.html
- lists.apple.com/archives/security-announce/2016/May/msg00002.html
- lists.apple.com/archives/security-announce/2016/May/msg00003.html
- lists.apple.com/archives/security-announce/2016/May/msg00004.html
- rhn.redhat.com/errata/RHSA-2016-2957.html
- www.oracle.com/technetwork/topics/security/bulletinjul2016-3090568.html
- www.oracle.com/technetwork/topics/security/linuxbulletinjul2016-3090544.html
- www.oracle.com/technetwork/topics/security/ovmbulletinjul2016-3090546.html
- www.securityfocus.com/bid/90691
- www.securitytracker.com/id/1035890
- www.ubuntu.com/usn/USN-2994-1
- xmlsoft.org/news.html
- access.redhat.com/errata/RHSA-2016:1292
- git.gnome.org/browse/libxml2/commit/?id=cbb271655cadeb8dbb258a64701d9a3a0c4835b4
- kc.mcafee.com/corporate/index?page=content&id=SB10170
- security.gentoo.org/glsa/201701-37
- support.apple.com/HT206564
- support.apple.com/HT206566
- support.apple.com/HT206567
- support.apple.com/HT206568
Vendor advisories and official records. Exploit/PoC links are deliberately left out.