libsmb2 before 6.3 Integer Overflow in DCE/RPC NDR Decoder via NetrShareEnum
Summary
| CVE | CVE-2026-115505 |
|---|---|
| State | PUBLISHED |
| Assigner | VulnCheck |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-10-22 20:17:06 UTC |
| Updated | 2026-10-22 20:17:06 UTC |
| Description | libsmb2 before 6.3 contains integer overflow vulnerabilities in the DCE/RPC NDR decoder in lib/dcerpc.c that allow heap out-of-bounds reads and writes. A malicious SMB server or machine-in-the-middle on unsigned connections can send crafted NetrShareEnum replies with wrapping actual_count or max_count values when clients call smb2_share_enum_async(), corrupting heap memory. |
Risk And Classification
Primary CVSS: v4.0 7.2 HIGH from [email protected]
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Problem Types: CWE-190 | CWE-190 Integer Overflow or Wraparound
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 4.0 | [email protected] | Secondary | 7.2 | HIGH | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N/E:X/C... |
| 4.0 | CNA | CVSS | 7.2 | HIGH | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N |
| 3.1 | [email protected] | Primary | 7.6 | HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:H |
| 3.1 | CNA | CVSS | 7.6 | HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:H |
CVSS v4.0 Breakdown
Attack Vector
NetworkAttack Complexity
LowAttack Requirements
NonePrivileges Required
NoneUser Interaction
PassiveConfidentiality
LowIntegrity
LowAvailability
HighSub Conf.
NoneSub Integrity
NoneSub Availability
NoneCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CVSS v3.1 Breakdown
Attack Vector
NetworkAttack Complexity
LowPrivileges Required
NoneUser Interaction
RequiredScope
UnchangedConfidentiality
LowIntegrity
LowAvailability
HighCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:H
Vendor Declared Affected Products
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| github.com/sahlberg/libsmb2 | [email protected] | github.com | |
| github.com/sahlberg/libsmb2/releases/tag/libsmb2-6.3 | [email protected] | github.com | |
| github.com/sahlberg/libsmb2/commit/a79f6914cb5ed3f74293d15cdea901261ce179ff | [email protected] | github.com | |
| www.vulncheck.com/advisories/libsmb2-before-6.3-integer-overflow-in-dce-rpc-ndr... | [email protected] | www.vulncheck.com | |
| github.com/sahlberg/libsmb2/issues/496 | [email protected] | github.com | |
| hackmd.io/@haindpwn/libsmb2-dcerpc-ndr-count-overflow-oob | [email protected] | hackmd.io | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
Vendor Comments And Credit
Discovery Credit
CNA: HaiND from the Post and Telecommunication Institute of Technology (en)
There are currently no legacy QID mappings associated with this CVE.