Malicious PDF — malware analysis report

Static analysis result for SHA-256 1e8c589eb508d7da…

MALICIOUS

PDF

94.0 KB Created: 2010-03-27 19:40:43 +04:00 Authoring application: Microsoft® Word 2010 First seen: 2026-05-11
MD5: d75f9787212efeae70a0940b79a08687 SHA-1: 4b9b6378b8f08bf54e58967613caa14d6253b91a SHA-256: 1e8c589eb508d7da1b1b3a9f710580e875a50115bb321587209d412316dbbf21
576 Risk Score

Malware Insights

MITRE ATT&CK
T1204.002 Malicious File T1059.001 PowerShell T1566.001 Spearphishing Attachment T1059.003 Windows Command Shell

The PDF file contains embedded JavaScript and a launch action that targets cmd.exe, indicating an attempt to execute a secondary payload. Specifically, the PDF leverages CVE-2010-1240 to launch cmd.exe with parameters that likely facilitate the execution of an embedded Windows executable payload, which is masqueraded as 'Barevner.pdf'. The ClamAV detection further confirms the malicious nature of the file.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 14

  • Adobe Reader Launch action command execution critical CVE exact CVE_2010_1240
    PDF uses the Adobe Reader/Acrobat Launch action pattern associated with CVE-2010-1240: cmd.exe is invoked with attacker-controlled parameters, paired with an embedded/exported payload.
  • TrueType bitmap font + active content — CVE-2023-26369 related high CVE related PDF_CVE_2023_26369_RELATED
    PDF embeds a TrueType font with bitmap tables (EBDT/sbix/CBDT) alongside exploit delivery indicators — CVE-2023-26369 exploits the sfac_GetSbitBitmap function in Adobe's libCoolType for arbitrary code execution. This CVE was actively exploited in the wild, but this rule does not validate the malformed EBLC/EBDT primitive.
  • ClamAV: Pdf.Tool.Agent-1388586 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Tool.Agent-1388586
  • Launch action critical PDF_LAUNCH
    PDF contains a /Launch action whose target is an executable, URL, or UNC path — can start an external application
  • Embedded Windows executable payload in PDF stream critical PDF_EMBEDDED_PE_PAYLOAD
    PDF stream bytes contain an embedded Windows executable with a verified PE header. Exploit chains often hide droppers inside ordinary streams rather than standard /EmbeddedFile attachments.
  • /Launch action target: cmd.exe critical PDF_LAUNCH_COMMAND
    PDF /Launch action specifies an executable target with parameters '/Q /C %HOMEDRIVE%&cd %HOMEPATH%&(if exist "Desktop\\Barevner.pdf" (cd "Desktop"' — references a known-dangerous executable (cmd, PowerShell, etc.).
  • Embedded attachment masquerades: declared document, content is windows-executable critical PDF_EMBEDDED_FILESPEC_CONTENT_MISMATCH
    An /EmbeddedFile attachment's declared filename extension or /Subtype MIME type contradicts the magic bytes of its decompressed content. The attachment is declared as a benign document or image but the bytes are an executable or executable-bearing archive. This is a deliberate deception used to hide droppers in PDF attachments and is a generic indicator of embed-and-drop weaponisation, independent of any specific CVE.
  • JavaScript action low 2 related findings PDF_JAVASCRIPT
    PDF contains a /JavaScript action. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • PDF JavaScript exploit cluster critical PDF_JS_EXPLOIT_CLUSTER
    PDF combines an executable JavaScript/action surface with exploit staging indicators such as eval/unescape/fromCharCode, XFA script content, or a related CVE pattern. Benign form JavaScript remains low-severity, but this correlated cluster is high-confidence malicious behavior.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • /Launch action paired with attachment-dropping JS API high PDF_LAUNCH_PLUS_DROPPER_JS
    PDF combines a /Launch action with a JavaScript API call that writes or opens an attached/external resource — the canonical shape of the CVE-2010-1240 /Launch + exportDataObject family. Benign PDFs do not pair these surfaces; the combination indicates a drop-and-execute chain regardless of the specific JS API knobs or /Launch target.
  • Suspicious extracted artifact medium EXTRACTED_FILE_STATIC_TRIAGE
    One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.
  • Embedded file low PDF_EMBEDDED
    PDF embeds a file attachment — could carry an executable or another weaponised document as a nested payload
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://www.microsoft.com/typography/ctfontshttp://fontfabrik.comYou In extracted file (stream_002_off000006ef.bin)
    • http://www.microsoft.com/typography/fonts/default.aspxIn extracted file (stream_002_off000006ef.bin)
    • http://crl.microsoft.com/pki/crl/products/CSPCA.crl0HIn extracted file (stream_002_off000006ef.bin)
    • http://www.microsoft.com/pki/certs/CSPCA.crt0In extracted file (stream_002_off000006ef.bin)
    • http://crl.microsoft.com/pki/crl/products/tspca.crl0HIn extracted file (stream_002_off000006ef.bin)
    • http://www.microsoft.com/pki/certs/tspca.crt0In extracted file (stream_002_off000006ef.bin)
    • http://www.microsoft.com/typographyIn extracted file (stream_002_off000006ef.bin)

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
Barevner.pdf pdf-embedded-file PDF EmbeddedFile object 20 at offset 0x13FAE 27136 bytes
SHA-256: 6c4e9e9486a931e6eeaa92d1f1cdde1ae45059e2081804220dacf6c22d771c91
Detection
ClamAV: No threats found
Obfuscation or payload: likely
actual_type=PE; declared_or_context_type=PDF; filename=Barevner.pdf; kind=pdf-embedded-file Static shellcode analysis found candidate code region(s). Indicators: NOP sled, SC_PEB_ACCESS, SC_STR_GETPROCADDRESS Static shellcode analysis recovered API/import strings: LoadLibraryExA, GetProcAddress, ExitProcess
javascript_obj0021_000.js pdf-javascript-stream PDF /JS object 21 at offset 0x173A6 57 bytes
SHA-256: 37912f45e0dc16a79f991b448580332d0a1d70971afda802255e17d9e4ed98e3
Preview script
First 1,000 lines of the extracted script
this.exportDataObject({ cName: "Barevner", nLaunch: 0 });
stream_002_off000006ef.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x6EF 171816 bytes
SHA-256: 1f9bda0f357b2943216affe7146442b959e081c45be125d57db32e1b3f146674