Malicious PDF — malware analysis report

Static analysis result for SHA-256 9de40586b4dd0839…

MALICIOUS

PDF

720.7 KB Created: 2015-02-09 17:43:42 +00:00 Authoring application: Microsoft® Word 2010 First seen: 2026-05-04
MD5: a2f22c8a26361e3883e728e3733884fa SHA-1: fde4bc8d90d9eaa3ac8be3be4898824e6d92694a SHA-256: 9de40586b4dd083999a4d0120b9ea750c95ce43ae4e17531a1f43e1dbd3df797
658 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1059.007 Command and Scripting Interpreter: JavaScript T1105 Ingress Tool Transfer T1566.001 Phishing: Spearphishing Attachment

The PDF contains JavaScript that uses the exportDataObject function to launch cmd.exe, which then attempts to execute the embedded file 'interesting-facts.pdf'. This file is detected by ClamAV as a Windows executable (Win.Trojan.MSShellcode-7), indicating it's likely a second-stage payload. The PDF also leverages CVE-2010-1240 and CVE-2023-26369 for execution and payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9916

Heuristics 15

  • 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.Dropper.Agent-7287064-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Dropper.Agent-7287064-0
  • Launch action critical PDF_LAUNCH
    PDF contains a /Launch action whose target is an executable, URL, or UNC path — can start an external application
  • /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\\interesting-facts.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.
  • Suspicious extracted artifact critical 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.
  • 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.
  • Clickable PDF combines external action with parser-evasion structure high PDF_ACTION_PARSER_EVASION
    PDF has an external clickable URI together with object graph or xref structures that make parsers disagree, such as divergent duplicate objects, parser divergence, or xref offset mismatch. That combination is stronger than a plain link: the document is both an outward-action carrier and a parser-confusion/evasion sample.
  • Embedded file low PDF_EMBEDDED
    PDF embeds a file attachment — could carry an executable or another weaponised document as a nested payload
  • External URI info PDF_URI
    PDF contains an external URL action
  • 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.bloomsbury-international.com/en/ PDF link annotation
    • http://www.bloomsbury-international.com/en/courses.htmlIn PDF document text
    • http://www.bloomsbury-international.com/en/courses/english-for-specific-purposes.htmlIn PDF document text
    • http://www.gettyimages.com��In PDF document text
    • http://ns.useplus.org/ldf/xmp/1.0/In PDF document text
    • http://www.zeustech.net/In extracted file (interesting-facts.pdf)
    • http://]hostname[:port]/pathIn extracted file (interesting-facts.pdf)
    • tcp://192.168.1.7:4444In extracted file (interesting-facts.pdf)
    • https://www.facebook.com/bloomsburyinternationalIn PDF document text
    • https://twitter.com/BloomsburyIntlIn PDF document text
    • https://plus.google.com/b/103611162292392072892/+Bloomsbury-international/postsIn PDF document text
    • http://dictionary.cambridge.org/In PDF document text
    • http://www.iec.chIn PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/photoshop/1.0/In PDF document text
    • http://www.gettyimages.comIn PDF document text
    • http://www.apache.org/In extracted file (interesting-facts.pdf)
    • http://www.microsoft.com/typography/ctfontshttp://fontfabrik.comYouIn extracted file (stream_039_off00079d62.bin)
    • http://www.microsoft.com/typography/fonts/default.aspxIn extracted file (stream_039_off00079d62.bin)
    • http://crl.microsoft.com/pki/crl/products/MicrosoftTimeStampPCA.crl0XIn extracted file (stream_039_off00079d62.bin)
    • http://www.microsoft.com/pki/certs/MicrosoftTimeStampPCA.crt0In extracted file (stream_039_off00079d62.bin)
    • http://crl.microsoft.com/pki/crl/products/MicCodSigPCA_08-31-2010.crl0ZIn extracted file (stream_039_off00079d62.bin)
    • http://www.microsoft.com/pki/certs/MicCodSigPCA_08-31-2010.crt0In extracted file (stream_039_off00079d62.bin)
    • http://crl.microsoft.com/pki/crl/products/microsoftrootcert.crl0TIn extracted file (stream_039_off00079d62.bin)
    • http://www.microsoft.com/pki/certs/MicrosoftRootCert.crt0In extracted file (stream_039_off00079d62.bin)
    • http://www.microsoft.com/typographyIn extracted file (stream_039_off00079d62.bin)

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
interesting-facts.pdf pdf-embedded-file PDF EmbeddedFile object 440 at offset 0xA9004 73802 bytes
SHA-256: 8cc500662b4480fa55bfd329c5d96fd9b10d5c301eae8d7937ffc19402830fdc
Detection
ClamAV: Win.Trojan.MSShellcode-7
Obfuscation or payload: likely
actual_type=PE; declared_or_context_type=PDF; filename=interesting-facts.pdf; kind=pdf-embedded-file Static shellcode analysis recovered the Metasploit stager connect-back address: 192.168.1.7:4444 (reverse/x86, lab (non-routable)) Static shellcode analysis found candidate code region(s). Indicators: SC_PEB_ACCESS, SC_MSF_REVERSE, SC_PUSH_STRING Static shellcode analysis recovered API/import strings: kernel32.dll, advapi32.dll, KERNEL32.DLL, ADVAPI32.DLL, LoadLibraryA, GetProcAddress
javascript_obj0441_000.js pdf-javascript-stream PDF /JS object 441 at offset 0xB3CAE 66 bytes
SHA-256: 6286ec33493f22a414774d6c8a6080048bf19b0204aacb445281f01ebc08bc94
Preview script
First 1,000 lines of the extracted script
this.exportDataObject({ cName: "interesting-facts", nLaunch: 0 });
stream_039_off00079d62.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x79D62 191424 bytes
SHA-256: 76a8472ca10bac106dcc23fefc3d531faf4fdae18b7c679b44891eeebcd10e7a
font_01_sfnt_off00090526.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x90526 188628 bytes
SHA-256: 157d21979f4e67ad6884cae215dbe2964ac9146ecc72623380852e14494e1eef