CVE-2026-111137: medium-severity vulnerability in amartin755 libsmi
libsmi through 0.5.0 Out-of-Bounds Write via smiValueAsString OCTET STRING DEFVAL
Published · Updated
33Vexday Risk Score
No sign of exploitation. It has a public proof of concept.
ssvc Attendcvss 6.9epss 0.1%
exploitation probability
0.1%top 98% of all CVEs
observed exploitation
nono source reports it
1 public exploit(s)
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.
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N
Affected products
amartin755 · libsmipublic PoCs found — 1
cve_referencehackmd.io/@haind-pwn/libsmi-smivalueasstring-octetstring-defval-oob-writeunverified⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.
References
https://github.com/amartin755/libsmihttps://github.com/amartin755/libsmi/blob/c58307210fe995ec419db976eb234aebc71a9216/lib/smi.c#L479-L566https://hackmd.io/@haind-pwn/libsmi-smivalueasstring-octetstring-defval-oob-writehttps://www.vulncheck.com/advisories/libsmi-through-0.5.0-out-of-bounds-write-via-smivalueasstring-octet-string-defval