The htmlParseComment function in HTMLparser.c in libxml2 allows attackers to obtain sensitive information, cause a denial of service (out-of
The htmlParseComment function in HTMLparser.c in libxml2 allows attackers to obtain sensitive information, cause a denial of service (out-of-bounds heap memory access and application crash), or possibly have unspecified other impact via an unclosed HTML comment.
- Published
- Apr 11, 2016
- Updated
- Jun 16, 2026
- EPSS
- 4.9% · 92th percentile
- CWE
- CWE-119
Sign in to follow · You’ll be notified if a followed record enters KEV, gets an exploit or is updated.
Report tools
Action score
40
Plan
Add it to your regular patch cycle.
- CVSS
- 39 / 40 · 9.8 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 1 / 30 · 4.9%
Affected systems
| Vendor | Product | CPE |
|---|---|---|
| xmlsoft | libxml2 | cpe:2.3:a:xmlsoft:libxml2 |
| debian | debian linux | cpe:2.3:o:debian:debian_linux |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- debian debian linux7.0
- debian debian linux8.0
- debian debian linux9.0
- xmlsoft libxml2before 2.9.3
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+really2.9.1+dfsg1-0.1 | 2.9.2+really2.9.1+dfsg1-0.1 |
| Debian:6.0 | libxml2 | before 2.7.8.dfsg-2+squeeze12 | 2.7.8.dfsg-2+squeeze12 |
| Debian:7 | libxml2 | before 2.8.0+dfsg1-7+wheezy5 | 2.8.0+dfsg1-7+wheezy5 |
| Debian:8 | libxml2 | before 2.9.1+dfsg1-5+deb8u1 | 2.9.1+dfsg1-5+deb8u1 |
| Red Hat:enterprise_linux:6::client | libxml2 | before 0:2.7.6-20.el6_7.1 | 0:2.7.6-20.el6_7.1 |
| Red Hat:enterprise_linux:6::client | libxml2-debuginfo | before 0:2.7.6-20.el6_7.1 | 0:2.7.6-20.el6_7.1 |
| Red Hat:enterprise_linux:6::client | libxml2-devel | before 0:2.7.6-20.el6_7.1 | 0:2.7.6-20.el6_7.1 |
| Red Hat:enterprise_linux:6::client | libxml2-python | before 0:2.7.6-20.el6_7.1 | 0:2.7.6-20.el6_7.1 |
| Red Hat:enterprise_linux:6::client | libxml2-static | before 0:2.7.6-20.el6_7.1 | 0:2.7.6-20.el6_7.1 |
| Red Hat:enterprise_linux:7::client | libxml2 | before 0:2.9.1-6.el7_2.2 | 0:2.9.1-6.el7_2.2 |
| Red Hat:enterprise_linux:7::client | libxml2-debuginfo | before 0:2.9.1-6.el7_2.2 | 0:2.9.1-6.el7_2.2 |
| Red Hat:enterprise_linux:7::client | libxml2-devel | before 0:2.9.1-6.el7_2.2 | 0:2.9.1-6.el7_2.2 |
| Red Hat:enterprise_linux:7::client | libxml2-python | before 0:2.9.1-6.el7_2.2 | 0:2.9.1-6.el7_2.2 |
| Red Hat:enterprise_linux:7::client | libxml2-static | before 0:2.9.1-6.el7_2.2 | 0:2.9.1-6.el7_2.2 |
| SUSE:Linux Enterprise Desktop 11 SP3 | libxml2-python | before 2.7.6-0.37.4 | 2.7.6-0.37.4 |
| SUSE:Linux Enterprise Desktop 12 | libxml2 | before 2.9.1-17.1 | 2.9.1-17.1 |
| SUSE:Linux Enterprise Desktop 12 | python-libxml2 | before 2.9.1-17.1 | 2.9.1-17.1 |
| SUSE:Linux Enterprise Software Development Kit 11 SP3 | libxml2 | before 2.7.6-0.37.1 | 2.7.6-0.37.1 |
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+really2.9.1+dfsg1-0.1 · Debian:12 | Package registry (OSV) |
| red hat:libxml2 | 0:2.7.6-20.el6_7.1 · Red Hat:enterprise_linux:6::client | Package registry (OSV) |
| red hat:libxml2-debuginfo | 0:2.7.6-20.el6_7.1 · Red Hat:enterprise_linux:6::client | Package registry (OSV) |
| red hat:libxml2-devel | 0:2.7.6-20.el6_7.1 · Red Hat:enterprise_linux:6::client | Package registry (OSV) |
| red hat:libxml2-python | 0:2.7.6-20.el6_7.1 · Red Hat:enterprise_linux:6::client | Package registry (OSV) |
| red hat:libxml2-static | 0:2.7.6-20.el6_7.1 · Red Hat:enterprise_linux:6::client | Package registry (OSV) |
| suse:libxml2 | 2.9.1-17.1 · SUSE:Linux Enterprise Desktop 12 | Package registry (OSV) |
| suse:libxml2-python | 2.7.6-0.37.4 · SUSE:Linux Enterprise Desktop 11 SP3 | Package registry (OSV) |
| suse:python-libxml2 | 2.9.1-17.1 · SUSE:Linux Enterprise Desktop 12 | Package registry (OSV) |
Exploit status
Proof of concept available
A public proof of concept or detection signature exists. Exploit knowledge is out there; don't delay patching.
Evidence
- Proof-of-concept repository on GitHub ×1
Noroxi does not host or link to exploit code. Metasploit module names and Nuclei template ids are shown (names, not code); Exploit-DB entries and PoC repositories are given as counts only.
| Source | Kind | Date |
|---|---|---|
| Proof-of-concept repository on GitHub | stars:1 | 2016-03-17 |
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.
- First PoC-26 d
- Published
- TodaySep 30, 2026+3824 d
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.
- No user action is required.
- 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
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- 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:3.1/AV:N/AC:L/PR:N/UI:N/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
- rhn.redhat.com/errata/RHSA-2016-1089.html
- www.debian.org/security/2015/dsa-3430
- www.openwall.com/lists/oss-security/2015/04/19/4
- www.openwall.com/lists/oss-security/2015/09/13/1
- www.openwall.com/lists/oss-security/2015/12/31/7
- www.securityfocus.com/bid/79811
- bugzilla.gnome.org/show_bug.cgi?id=746048
- git.gnome.org/browse/libxml2/commit/?id=e724879d964d774df9b7969fc846605aa1bac54c
- hackerone.com/reports/57125#activity-384861
Vendor advisories and official records. Exploit/PoC links are deliberately left out.