Is grid.pdf safe?
No antivirus engine detected this long-observed PDF, while one sandbox produced concerning technique mappings that lack malicious-verdict or network-reputation corroboration.
All 77 antivirus engines returned no detection, including 18 tier-1 engines, and the file has been observed since 2011. One sandbox mapped credential dumping, process injection, and data destruction techniques, but issued no malicious verdict; the two contacted IP addresses were not reputation-checked.
05254dd9bed9a81d2c…02a91ae835e5d5Recommended next actions
Before opening
Open it only when its sender or download source is one you independently trust.
If you already opened it
Keep normal device protection enabled and stop if the file behaves unexpectedly.
Intelligence
The saved assessment, checked against the scan evidence and recorded coverage.
The reasoning behind this verdict
This section explains the evidence supporting the verdict and keeps conflicting or missing signals visible.
All 77 antivirus engines returned no detection, including 18 tier-1 engines, and the file has been observed since 2011. One sandbox mapped credential dumping, process injection, and data destruction techniques, but issued no malicious verdict; the two contacted IP addresses were not reputation-checked.
The strongest evidence is the complete absence of detections across 77 antivirus engines, including 18 tier-1 engines. The PDF has also been known since 2011, which reduces concern that it is an unrecognized newly distributed sample. One completed sandbox run mapped T1003, T1055, and T1485, so those behavioral signals cannot be ignored. However, that run produced no malicious sandbox verdict, and the recorded process activity largely involved Adobe Acrobat components. The nine dropped files had no malicious child result, although their individual verdicts remained unknown. Because reputation checks for the two contacted IP addresses were unavailable, the no complete contacted-host reputation result was available.
What We Detected
No detections were returned by 77 antivirus engines, including 18 tier-1 engines. The PDF was first submitted in December 2011 and has appeared in 13 submissions from 10 sources, providing a long observation history.
Threat Behavior
One sandbox run mapped activity to T1003, T1055, and T1485, corresponding to credential access, process injection, and data destruction categories. These mappings are concerning, but the sandbox did not issue a malicious verdict, and recorded processes primarily involved Adobe Acrobat, crash-reporting, and updater components. Nine dropped files were inspected without a malicious child finding, though all nine remained unclassified. The run contacted 18.213.11.84 and 92.123.124.167 directly; because contactedHosts is unavailable, no complete reputation conclusion can be drawn for those addresses.
What To Do Now
Open the document only with a fully updated PDF reader and keep endpoint protection enabled. If the document arrived unexpectedly or requests unusual interaction, verify its source before opening and consider viewing it in a restricted environment.
Where this verdict could be wrong3 caveats
- The T1003, T1055, and T1485 mappings are meaningful counter-signals despite the complete absence of antivirus detections.
- Nine dropped children were inspected without a malicious result, but droppedChildren.rollup.unknown=9 means none received a confirmed benign verdict.
- Direct-IP contacts to 18.213.11.84 and 92.123.124.167 cannot be characterized as benign because contactedHosts=null.
These are the assessment's weak points. If you believe one applies to your file, report the verdict and we'll re-review it.
- 0/77 antivirus engines reported a detection.
- All 18 tier-1 engines reported no detection.
- behaviour.hasMaliciousSandboxVerdict=false.
- droppedChildren.hasMaliciousChild=false.
- The sample has been observed since 2011-12-04.
- One sandbox mapped offensive techniques T1003, T1055, and T1485.
- Direct-IP traffic reached 18.213.11.84 and 92.123.124.167 without a completed reputation cross-check.
- All nine inspected dropped children have unknown individual verdicts.
Use an updated PDF reader and keep endpoint protection enabled. Verify the sender or download source if the document was unsolicited, particularly because the sandbox technique mappings and IP reputation remain unresolved.
Coverage & freshness
Complete means the check returned a usable result. It does not mean the file is safe.
Antivirus
Complete0 of 77 engines flagged the file.
Sandbox
Complete1 isolated runtime environment contributed observations.
Network
Partial2 runtime contacts were observed without a completed reputation cross-check.
YARA
Complete3 signature or behavior rules matched.
External intel
Complete3 of 3 independent reference sources completed.
Behavior
Plain-English impact first, then the observed runtime evidence.
Runtime flight recorder
Capture complete- 1isolated sandbox run
- 12MITRE ATT&CK techniques
- 7spawned processes
- 2network contacts
- 40filesystem & mutex artifacts
Attack story
Runtime observations grouped by analysis stage. Arrows organize the stages; they do not claim chronology or causality.
Input file
The submitted object
- FileObserved
grid.pdf
05254dd9bed9a81d2c9da60e40bfe77b89e6b757428cc363a802a91ae835e5d5
01Uploaded file
Processes
Runtime execution
- ProcessObserved
Observed process
"C:\Program Files\Adobe\Acrobat DC\Acrobat\Adobe Crash Processor.exe"
02Isolated runtime analysis - ProcessObserved
Observed process
"C:\Program Files\Adobe\Acrobat DC\Acrobat\CRWindowsClientService.exe" "C:\Program Files\Adobe\Acrobat DC\Acrobat" updatepvbpreference 182d2756-74e9-4002-9504-06b101fe2ca2 0 0
03Isolated runtime analysis - +1 more recorded observation in Analyst mode
Files
Created or changed
- Written fileObserved
acroNGLLog.txt
C:\Users\<USER>\AppData\Local\Temp\acroNGLLog.txt
04Isolated runtime analysis - Written fileObserved
NGLClient_AcrobatReader123.8.20533.6.log
C:\Users\<USER>\AppData\Local\Temp\NGL\NGLClient_AcrobatReader123.8.20533.6.log
05Isolated runtime analysis - +1 more recorded observation in Analyst mode
Network
Hosts contacted
- Contacted hostObserved
18.213.11.84
Contact observed during runtime.
06Isolated runtime analysis - Contacted hostObserved
92.123.124.167
Contact observed during runtime.
07Isolated runtime analysis - +1 more recorded observation in Analyst mode
7 recorded facts from one runtime window. Every fact remains independently traceable in Analyst mode.
What this file did when executed
This file was detonated in 1 sandbox and its runtime behaviour was observed.
Adversary techniques mapped to the MITRE ATT&CK framework.
- 18.213.11.84
- 92.123.124.167
- C:\Users\<USER>\AppData\Local\Temp\acroNGLLog.txt
- C:\Users\<USER>\AppData\Local\Temp\NGL\NGLClient_AcrobatReader123.8.20533.6.log
- C:\Users\<USER>\AppData\Local\Temp\Tmp8CD5.tmp
- C:\Users\<USER>\AppData\Local\Temp\Tmp94D4.tmp
- C:\Users\<USER>\AppData\Local\Temp\A9gklp14_ow7duh_2co.tmp
- C:\Users\<USER>\AppData\Roaming\Adobe\Acrobat\DC\JSCache\GlobSettings
- C:\Users\<USER>\AppData\Roaming\Adobe\Acrobat\9.0\SharedDataEvents-journal
- C:\Users\user\AppData\LocalLow\Adobe\AcroCef\DC\Acrobat\Cache\Code Cache\js\05349744be1ad4ad_0
- C:\Users\user\AppData\LocalLow\Adobe\AcroCef\DC\Acrobat\Cache\Code Cache\js\0786087c3c360803_0
- C:\Users\user\AppData\LocalLow\Adobe\AcroCef\DC\Acrobat\Cache\Code Cache\js\0998db3a32ab3f41_0
- Global\AdobeCrashProcessorLocalLowLock
- Local\ZonesCacheCounterMutex
- Local\ZonesLockedCacheCounterMutex
- Local\Acrobat Instance Mutex
- Local\SessionImmersiveColorMutex
Files this sample writes at runtime
This file drops 9 children at runtime. None are currently flagged malicious in our cache.
- 9bdf729c1be06f906830…9fab46Never scannednever seen before
- 610bd324afb0f74bf298…54abb5Never scannednever seen before
- 61c2182963cb70e80ec5…c09db8Never scannednever seen before
- 2a5ca8e58611ce578c79…c37f4dNever scannednever seen before
- fb31c005f753898e7f54…c06c6eNever scannednever seen before
- 7a8b7fdb56fef49842d9…019e3dNever scannednever seen before
- 621e93b240c5d58e7089…0209e1Never scannednever seen before
- 4346319202f1fef1e1ec…5f37d3Never scannednever seen before
- 064d9f17752a49aa80c8…671928Never scannednever seen before
Detection & Forensics
Consensus, attribution, signatures, code structure, prevalence, and identity.
Evidence integrity
Chain of custody for the facts preserved in this report.
- 3rule hits recorded
- 0 / 77engines flagged
- 10sources in submission history
Why these facts are shown
Each statement identifies whether it was directly recorded or derived from saved scan facts.
- 01
0 of 77 antivirus engines flagged the file.
Verdict inputView chapterProvenanceObservedSourceAntivirus analysisObserved at - 02
1 high-confidence signature or behavior rule matched this file.
Verdict inputView chapterProvenanceDerivedSourceSignature and behavior rulesObserved at - 03
The hash has been submitted 13 times from 10 sources.
ProvenanceDerivedSourceSaved report factsObserved at - 04
Scanned file: grid.pdf — 05254dd9bed9a81d2c9da60e40bfe77b89e6b757428cc363a802a91ae835e5d5
ProvenanceObservedSourceUploaded fileObserved at - 05
Observed process — "C:\Program Files\Adobe\Acrobat DC\Acrobat\Adobe Crash Processor.exe"
ProvenanceObservedSourceIsolated runtime analysisObserved at - 06
Observed process — "C:\Program Files\Adobe\Acrobat DC\Acrobat\CRWindowsClientService.exe" "C:\Program Files\Adobe\Acrobat DC\Acrobat" updatepvbpreference 182d2756-74e9-4002-9504-06b101fe2ca2 0 0
ProvenanceObservedSourceIsolated runtime analysisObserved at - 07
File written: acroNGLLog.txt — C:\Users\<USER>\AppData\Local\Temp\acroNGLLog.txt
ProvenanceObservedSourceIsolated runtime analysisObserved at - 08
File written: NGLClient_AcrobatReader123.8.20533.6.log — C:\Users\<USER>\AppData\Local\Temp\NGL\NGLClient_AcrobatReader123.8.20533.6.log
ProvenanceObservedSourceIsolated runtime analysisObserved at - 09
Contacted host: 18.213.11.84 — Contact observed during runtime.
ProvenanceObservedSourceIsolated runtime analysisObserved at - 10
Contacted host: 92.123.124.167 — Contact observed during runtime.
ProvenanceObservedSourceIsolated runtime analysisObserved at
Detection sources at a glance
The available sources did not agree on a named threat category.
MalwareBazaar, YARAify, and CIRCL hashlookup completed and returned no entries for this hash.
Signatures and behavior heuristics
A community signature or high-severity behavioral heuristic matched. Signatures identify known patterns; heuristics are strong leads but are not proof on their own.
The saved runtime evidence maps this activity to MITRE T1055 (Process Injection). The mapping supports possible process injection, but it does not prove the exact injection method or the operator's intent.
Evidence"C:\Program Files\Adobe\Acrobat DC\Acrobat\Adobe Crash Processor.exe"MITRE T1003 (OS Credential Dumping) mapped by at least one sandbox run.
The sample contacted an external IP address directly and no application domain was recorded. Direct-IP traffic also occurs in legitimate installers and infrastructure, so this is supporting context only and requires corroboration from host reputation and other runtime evidence.
Evidence18.213.11.84 · 92.123.124.167
0 of 77 engines flagged this file
View all 77 engine results
PE structure
Not applicablePE structure analysis applies to Windows executable formats, not this file type.
How widely this file has been seen
Moderate prevalence — neither rare nor common. No strong prior applies.
Fingerprint and provenance
- File name
- grid.pdf
- Format
- Code signing
- Not applicable to this file type
- Size
- 16.9 KB
- Last analyzed
- Sep 9, 2026, 8:55 PM UTC
05254dd9bed9a81d2c9da60e40bfe77b89e6b757428cc363a802a91ae835e5d5Safety & FAQ
Complete recovery guidance and answers for the next decision.
What to do now
This file appears low risk based on the evidence available now.
- Recovery step 01
Open it only when its sender or download source is one you independently trust.
- Recovery step 02
A clean result reduces known risk, but it cannot guarantee that every new or targeted threat has been detected.
- Recovery step 03
Keep your antivirus and Windows updates switched on so you stay protected.
Safety FAQ
Direct answers grounded in the saved verdict and evidence in this report.
Is grid.pdf safe?
What is grid.pdf?
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Community
Member reviews and reports for this exact file hash.