libsmi through 0.5.0 contains an out-of-bounds write vulnerability in smiValueAsString() in lib/smi.c that allows attackers to overflow a fixed 1024-byte static buffer through hex rendering of OCTET STRING values
Affects libsmiSource GCVE Database
Not known to be exploited · CVSS 6.9 Medium.
Data as of 28 Oct 2026, 22:31 UTC
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:H/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 15 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 26.10libsmipkg:deb/ubuntu/libsmi?arch=source&distro=stonkingOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlibsmipkg:deb/ubuntu/libsmi?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSlibsmipkg:deb/ubuntu/libsmi?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 22.04 LTSlibsmipkg:deb/ubuntu/libsmi?arch=source&distro=jammyOther threats | Affected
| Fixed in– |
Ubuntu 20.04 LTSlibsmipkg:deb/ubuntu/libsmi?arch=source&distro=focalOther threats | Affected
| Fixed in– |
Ubuntu 18.04 LTSlibsmipkg:deb/ubuntu/libsmi?arch=source&distro=bionicOther 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
libsmi through 0.5.0 contains an out-of-bounds write vulnerability in smiValueAsString() in lib/smi.c that allows attackers to overflow a fixed 1024-byte static buffer through hex rendering of OCTET STRING values. Attackers can supply a crafted MIB with an OCTET STRING DEFVAL of 512 or more octets and a leading 0x00 byte to corrupt adjacent library globals and crash smidump or other consumers.
References
- ubuntu.com/security/CVE-2026-111137 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-111137 (opens in a new tab)
- github.com/amartin755/libsmi (opens in a new tab)
- github.com/amartin755/libsmi/blob/c58307210fe995ec419db976eb234aebc71a9216/lib/smi.c (opens in a new tab)
- hackmd.io/@haind-pwn/libsmi-smivalueasstring-octetstring-defval-oob-write (opens in a new tab)
- vulncheck.com/advisories/libsmi-through-0.5.0-out-of-bounds-write-via-smivalueasstring-octet-string-defval (opens in a new tab)