The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - smb: client: fix OOB reads parsing symlink error response When a CREATE returns STATUS_STOPPED_ON_SYMLINK,     smb2_check_message() returns success without any length validation, leaving the symlink parsers as the     only defense against an untrusted server. symlink_data() walks SMB 3.1.1 error contexts with the loop test     p < end, but reads p->ErrorId at offset 4 and p->ErrorDataLength at offset 0. When the server-controlled     ErrorDataLength advances p to within 1-7 bytes of end, the next iteration will read past it. When the     matching context is found, sym->SymLinkErrorTag is read at offset 4 from p->ErrorContextData with no check     that the symlink header itself fits. smb2_parse_symlink_response() then bounds-checks the substitute name     using SMB2_SYMLINK_STRUCT_SIZE as the offset of PathBuffer from iov_base. That value is computed as     sizeof(smb2_err_rsp) + sizeof(smb2_symlink_err_rsp), which is correct only when ErrorContextCount == 0.
    With at least one error context the symlink data sits 8 bytes deeper, and each skipped non-matching     context shifts it further by 8 + ALIGN(ErrorDataLength, 8). The check is too short, allowing the     substitute name read to run past iov_len. The out-of-bound heap bytes are UTF-16-decoded into the symlink     target and returned to userspace via readlink(2). Fix this all up by making the loops test require the     full context header to fit, rejecting sym if its header runs past end, and bound the substitute name     against the actual position of sym->PathBuffer rather than a fixed offset. Because sub_offs and sub_len     are 16bits, the pointer math will not overflow here with the new greater-than. (CVE-2026-31613)

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Linux Distros Unpatched Vulnerability : CVE-2026-31613

high Nessus Plugin ID 310311

Version 1.4