{"record":{"id":"9696030b4a76619d","repo":"moonD4rk/HackBrowserData","slug":"failed-to-find-malloc-small-regions-w","errorCode":null,"errorMessage":"failed to find malloc small regions: %w","messagePattern":"failed to find malloc small regions: %w","errorType":"exception","errorClass":null,"httpStatus":null,"severity":"error","filePath":"masterkey/gcoredump_darwin.go","lineNumber":88,"sourceCode":"\tpid, err := findProcessByName(\"securityd\", true)\n\tif err != nil {\n\t\treturn nil, fmt.Errorf(\"failed to find securityd pid: %w\", err)\n\t}\n\n\t// gcore appends \".PID\" to the -o prefix, e.g. prefix.123\n\tcorePrefix := filepath.Join(os.TempDir(), fmt.Sprintf(\"securityd-core-%d\", time.Now().UnixNano()))\n\tcorePath := fmt.Sprintf(\"%s.%d\", corePrefix, pid)\n\tdefer os.Remove(corePath)\n\n\tcmd := exec.Command(\"gcore\", \"-d\", \"-s\", \"-v\", \"-o\", corePrefix, strconv.Itoa(pid))\n\tif err := cmd.Run(); err != nil {\n\t\treturn nil, fmt.Errorf(\"failed to dump securityd memory: %w\", err)\n\t}\n\n\t// vmmap identifies MALLOC_SMALL heap regions where securityd stores keys\n\tregions, err := findMallocSmallRegions(pid)\n\tif err != nil {\n\t\treturn nil, fmt.Errorf(\"failed to find malloc small regions: %w\", err)\n\t}\n\n\tcandidates, err := scanMasterKeyCandidates(corePath, regions)\n\tif err != nil {\n\t\treturn nil, fmt.Errorf(\"scan master key candidates: %w\", err)\n\t}\n\tif len(candidates) == 0 {\n\t\treturn nil, fmt.Errorf(\"no master key candidates found in securityd memory\")\n\t}\n\n\t// read keychain file once, reuse buffer for each candidate\n\tkeychainBuf, err := os.ReadFile(loginKeychainPath)\n\tif err != nil {\n\t\treturn nil, fmt.Errorf(\"read keychain: %w\", err)\n\t}\n\n\tfor _, candidate := range candidates {\n\t\tkc, err := keychainbreaker.Open(keychainbreaker.WithBytes(keychainBuf))","sourceCodeStart":70,"sourceCodeEnd":106,"githubUrl":"https://github.com/moonD4rk/HackBrowserData/blob/0503d04d7a8d0379d060268a74f1b149e5a0aad5/masterkey/gcoredump_darwin.go#L70-L106","documentation":"This wraps failures from findMallocSmallRegions(pid), which runs `vmmap --wide <pid>` and parses MALLOC_SMALL region lines. If vmmap fails to run (nonzero exit) the raw error propagates; note that vmmap succeeding but yielding zero MALLOC_SMALL regions returns an empty slice with no error, leading downstream to error 55 instead.","triggerScenarios":"Calling DecryptKeychainRecords as root when `vmmap --wide <pid>` exits nonzero — vmmap not installed (needs Xcode), insufficient rights to inspect the target despite root, or the pid no longer existing by the time vmmap runs.","commonSituations":"Xcode Command Line Tools not installed (no vmmap); securityd exited/restarted between gcore and vmmap so the PID is stale; MDM/EDR blocking vmmap's task port access; parsing mismatch on a macOS version whose vmmap output format differs.","solutions":["Ensure vmmap is installed: `xcrun vmmap <pid>` (part of Xcode / Command Line Tools).","Confirm the securityd PID is still alive when vmmap runs (`ps -p <pid>`); re-fetch the PID if securityd restarted.","Run `sudo vmmap --wide <securityd-pid>` manually to see the underlying vmmap error.","Check vmmap output format on your macOS version — unexpected formats silently yield zero regions (which then surfaces as 'no master key candidates').","Verify no EDR policy blocks vmmap from reading task ports of system daemons."],"exampleFix":"// before\nregions, err := findMallocSmallRegions(pid)\nif err != nil {\n    return nil, fmt.Errorf(\"failed to find malloc small regions: %w\", err)\n}\n// after\nregions, err := findMallocSmallRegions(pid)\nif err != nil {\n    return nil, fmt.Errorf(\"failed to find malloc small regions: %w (is Xcode/vmmap installed and pid %d alive?)\", err, pid)\n}","handlingStrategy":"validation","validationCode":"if _, err := exec.LookPath(\"vmmap\"); err != nil {\n    return fmt.Errorf(\"vmmap not found; install Xcode\")\n}\nout, err := exec.Command(\"sudo\", \"vmmap\", \"--wide\", strconv.Itoa(pid)).Output()\nif err != nil || !strings.Contains(string(out), \"MALLOC_SMALL\") {\n    return fmt.Errorf(\"vmmap failed or no MALLOC_SMALL regions for pid\")\n}","typeGuard":null,"tryCatchPattern":"_, err := masterkey.DecryptKeychainRecords()\nif err != nil && strings.Contains(err.Error(), \"failed to find malloc small regions\") {\n    // verify vmmap installed and pid still alive\n}","preventionTips":["Install Xcode / Command Line Tools providing vmmap.","Re-check the PID is alive immediately before dumping (securityd may restart).","Sanity-check vmmap output format on the target macOS version.","Test `sudo vmmap --wide <pid>` manually in the environment first."],"tags":["macos","vmmap","external-command"],"backgroundTag":"command-not-found","analyzedSha":"0503d04d7a8d0379d060268a74f1b149e5a0aad5","analyzedAt":"2026-09-06T13:38:28.707Z","contentChangedAt":"2026-09-06T13:38:28.707Z","schemaVersion":2},"datasetVersion":"2026-09-14T05:17:10.506Z"}