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
Affects libsmb2Source GCVE Database
Not known to be exploited · CVSS 7.2 High.
Data as of 28 Oct 2026, 22:31 UTC
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:H/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 22 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.10libsmb2pkg:deb/ubuntu/libsmb2?arch=source&distro=stonkingOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlibsmb2pkg:deb/ubuntu/libsmb2?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
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.
References
- ubuntu.com/security/CVE-2026-115505 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-115505 (opens in a new tab)
- github.com/sahlberg/libsmb2 (opens in a new tab)
- github.com/sahlberg/libsmb2/commit/a79f6914cb5ed3f74293d15cdea901261ce179ff (opens in a new tab)
- github.com/sahlberg/libsmb2/issues/496 (opens in a new tab)
- github.com/sahlberg/libsmb2/releases/tag/libsmb2-6.3 (opens in a new tab)
- hackmd.io/@haindpwn/libsmb2-dcerpc-ndr-count-overflow-oob (opens in a new tab)
- vulncheck.com/advisories/libsmb2-before-6.3-integer-overflow-in-dce-rpc-ndr-decoder-via-netrshareenum (opens in a new tab)