Malicious PDF — malware analysis report

Static analysis result for SHA-256 6dc65421d7348b4a…

MALICIOUS

PDF

67.8 KB Created: 2021-10-01 15:48:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0ca2c6f85ed1609c23dcb41aec3535fe SHA-1: 7688884acde4454b2f2a67e3ef1ac33ef8a97f4e SHA-256: 6dc65421d7348b4aa2b0c18d0bbb98b763ccf7549ab67409aec2ead77116af21
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF is identified as malicious by ML classifiers and ClamAV, exhibiting characteristics of a phishing lure with an image-only design and clickable actions. It contains a link farm pointing to multiple compromised CMS upload directories, suggesting an attempt to distribute malicious content or redirect users to malicious sites. Although no scripts were explicitly extracted, the PDF structure and heuristic firings strongly indicate a malicious intent to deceive users.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Image-only document with action trigger (screenshot lure) medium PDF_IMAGE_LURE
    PDF has 1 image(s), only 0 text block(s), carries a click-outward action, and is only 67 KB — typical shape of a phishing lure where a full-page screenshot hides a clickable button that launches or submits to an attacker URL.
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • 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://unipell.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613141e62f763---66037888312.pdf
    • http://uitvaartverzorgingsindex.nl/images/uploads/53338211284.pdf
    • http://harryreichert.de/uploaded_pics/News/file/rixejukazodiguno.pdf
    • https://mgrenginiai.lt/ckfinder/userfiles/files/96639984641.pdf
    • http://www.dereformasenalicante.com/archivos/files/23652185163.pdf
    • http://wpscrm.in/uploaded_files/userfiles/files/zojikivotebobumorum.pdf
    • https://restavracia02.com/userfiles/file/dipaxogifukaxezorefoju.pdf
    • http://newbiesites.com/userfiles/file/31272484762.pdf
    • http://www.mtpartnersfl.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614a19f995b52---50948904222.pdf
    • http://apnschool.in/singhania/downloads/file/91970991270.pdf
    • https://vargyasnekonyveles.hu/kepek/other/file/54969019522.pdf
    • http://thebodyclubonline.com/userfiles/file/wutupomekemitaribir.pdf
    • http://jcbcharpentebois.com/ressource/site-image/files/wurezipifofevobusijuvuge.pdf
    • http://sherwoodchambergolf.com/ckfinder/userfiles/files/59050575125.pdf
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16150a3ba8a8ff---dadenenigovilonotawofodis.pdf
    • http://shinyoungvalve.com/userData/board/file/mabotaderaterepez.pdf
    • http://jamoncup.es/wp-content/plugins/formcraft/file-upload/server/content/files/1613447ae01419---zagolobifutosujalet.pdf
    • https://nikoljski.com/ckfinder/userfiles/files/jedojudeta.pdf
    • https://sportsslife.net/upload/ckfinder/files/18508722792.pdf
    • https://deconkhoemanh.com/wp-content/plugins/super-forms/uploads/php/files/umcu665g2umlh236iir3hg8hhf/26535659188.pdf
    • http://morecoredesign.com/images/imageUps/files/94381332705.pdf
    • https://protum.se/file/83172452975.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=spongebob+games+for+android
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000adb8.bin
bf5b9f64dda8055cd731ae2d99f3c081b09625e30feff8a036a9a87e80c41ac6
pdf-font-stream PDF embedded font (sfnt) at offset 0xADB8 10912 bytes
font_01_sfnt_off0000c685.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xC685 16792 bytes
font_02_sfnt_off0000de97.bin
b1d8bf3e56fab25002258012fb45b64e1010c9221191dabf43320997ed29980e
pdf-font-stream PDF embedded font (sfnt) at offset 0xDE97 14324 bytes