Vulnerability · Published Oct 22, 2026 · Assigned by VulnCheck
CVE-2026-115505libsmb2 before 6.3 Integer Overflow in DCE/RPC NDR Decoder via NetrShareEnum
High 7.6
In plain English
A high-severity integer overflow in libsmb2 from sahlberg. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 11% of all known vulnerabilities).
Severity (CVSS 3.1)7.6High
Exploit odds (30 days)0.2%top 89.1% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known
Official 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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:13 | libsmb2 | no fix listed | DEBIAN-CVE-2026-115505 |
| Debian:14 | libsmb2 | no fix listed | DEBIAN-CVE-2026-115505 |
| Ubuntu:26.04:LTS | libsmb2 | no fix listed | UBUNTU-CVE-2026-115505 |
| Ubuntu:26.10 | libsmb2 | no fix listed | UBUNTU-CVE-2026-115505 |
Affected products (as reported)
Weakness: CWE-190 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:H
References
- https://hackmd.io/@haindpwn/libsmb2-dcerpc-ndr-count-overflow-oob technical-description, exploit
- https://github.com/sahlberg/libsmb2/issues/496 issue-tracking
- https://github.com/sahlberg/libsmb2/commit/a79f6914cb5ed3f74293d15cdea901261ce179ff patch
- libsmb2 libsmb2-6.3 Release Notes release-notes
- https://github.com/sahlberg/libsmb2 product
- VulnCheck Advisory: libsmb2 before 6.3 Integer Overflow in DCE/RPC NDR Decoder via NetrShareEnum third-party-advisory