Malicious PDF — malware analysis report

Static analysis result for SHA-256 a77ae3eee2db111e…

MALICIOUS

PDF

82.7 KB Created: 2021-09-08 03:22:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: c9c4ac14eddbf30f8dddab5a26fdd444 SHA-1: 5c8d5e0921936702a7ff117ce810f5c3a0164607 SHA-256: a77ae3eee2db111ee8a54cb6b71f97ede99f7e2d278f0e8d43b9a4554384147b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains numerous links, many pointing to compromised WordPress sites, suggesting a link farm or redirection scheme. The document body is heavily obfuscated and unreadable, providing no direct user-facing content, but the heuristics strongly suggest malicious intent through link distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 https://www.akilciilacdernegi.com/ckfinder/userfiles/files/lamagitujodisiguloxaw.pdf In PDF document text
    • https://lixtech.com.tw/ckfinder/ckfiles/files/lajagufafufirosix.pdfIn PDF document text
    • http://boxshop.mn/userfiles/files/toxabutagara.pdfIn PDF document text
    • http://ccsctda.com/ckfinder/userfiles/files/20210808_100720.pdfIn PDF document text
    • http://icaalliance.org/filespath/files/20210813182040.pdfIn PDF document text
    • https://oneremote.ru/wp-content/plugins/super-forms/uploads/php/files/a276208d68633a11af85f50e93bf8004/poziriwesamuritemowupeka.pdfIn PDF document text
    • http://www.dramayaramendes.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607c7a235ea45---4725185839.pdfIn PDF document text
    • http://launensia.cz/ckfinder/userfiles/files/92552065999.pdfIn PDF document text
    • http://funkyspa.net/ckfinder/userfiles/files/jamerovu.pdfIn PDF document text
    • http://euredit-editions.com/userfiles/file/toladup.pdfIn PDF document text
    • http://lesmashclub.com/imgUpload/files/86035375471.pdfIn PDF document text
    • https://www.opdrrustukalac.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e77ca324094---logerobazisapezi.pdfIn PDF document text
    • http://benedictinoselrosal.org/ckfinder/userfiles/files/xibakegexexetumitilokof.pdfIn PDF document text
    • https://siam-royal-view.ru/data/files/tipenuvisepujeb.pdfIn PDF document text
    • https://hotelritariccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/160bfad6778a83---sifenunedavuxogavaseve.pdfIn PDF document text
    • http://brothersaluminium.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/160851a2eb24ef---kozawev.pdfIn PDF document text
    • http://ebrinteractive.com/userfiles/file/tusaxasavepanarod.pdfIn PDF document text
    • http://recamonde.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161078b605c900---86815330522.pdfIn PDF document text
    • https://vieiras.pt/imagensprodutos/file/31224743156.pdfIn PDF document text
    • http://orbitsecurity.qa/pro_mvp_tech/uploads/file/75558348545.pdfIn PDF document text
    • https://assurancemauricie.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c4232bd6b6e---xixowowutaditawofatinusi.pdfIn PDF document text
    • https://www.pharmaright.ca/wp-content/plugins/super-forms/uploads/php/files/ae3ikfs89jv05ei0oll741vf88/zarewimigugilodedidizunu.pdfIn PDF document text
    • http://wypelnienia.kratex.pl/wp-content/plugins/super-forms/uploads/php/files/7cdd2d121936c76f17fa30b02554c0b7/58237718184.pdfIn PDF document text
    • https://ocvirapuato.com.mx/wp-content/plugins/super-forms/uploads/php/files/3052b198fc99dd34782b81d80ec0ec64/fevagujiwezuputi.pdfIn PDF document text
    • http://anaminfo.com/attachfile/file/71245702131.pdfIn PDF document text
    • http://www.bestlifepolicy.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1608e17f0f0624---81434722503.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=sample+lesson+plan+in+science+pdfPDF link annotation
    • 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/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dec5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEC5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f6d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6D7 17712 bytes
SHA-256: a97700ff33bb236f467838391f097979208a54243d5c08ce2ef4b66526af943f
font_02_sfnt_off000124b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x124B8 10656 bytes
SHA-256: bce98ee159fe0cb47b24a67f25581a0a8abd8547df3752606ed7888afa15021d