MEDIUM
CVE-2026-56404
CWE-190Published: June 21, 2026· Updated: Jun 23, 2026
6.9
CVSS v3.1
EPSS:0.10%probability of exploitation in 30 daysPercentile:1.2th
Official Description
libexpat before 2.8.2 has an integer overflow in addBinding.
Technical Analysis
CVE-2026-56404 requires local access, meaning attackers must already have a foothold on the target system.
The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.
A successful exploit results in complete confidentiality breach (data exposure), full integrity compromise (data manipulation), with a CVSS base score of 6.9.
CVSS v3.1 Vector Breakdown
Exploitability
Attack VectorLocal
Attack ComplexityHigh
Privileges Req.None
User InteractionNone
ScopeUnchanged
Impact
ConfidentialityHigh
IntegrityHigh
AvailabilityLow
CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:L
Affected Vendors & Products
libexpat_project1 product
libexpat
Source: NVD CPE · 1 total CPE entries
Exploit & PoC Resources
NO KNOWN EXPLOITNo public exploit confirmed at this time
Exploit-DB
Offensive Security exploit database
GitHub PoC Search
Community PoC repositories
Rapid7 / Metasploit
Metasploit module search
PacketStorm
Security advisories & exploits
NVD Detail
Official NIST entry
MITRE CVE
CVE Program entry
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Official Patches & Advisories
All References (1)
Quick Facts
CVE IDCVE-2026-56404
CVSS Score6.9 / 10
SeverityMEDIUM
WeaknessCWE-190
CISA KEVNo
EPSS (30d)0.10%
Affected1 vendor
PublishedJun 21, 2026
Related CVEs (CWE-190)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2026-56404 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWATCH.COM. CVE data is provided under the NVD usage policy.