Malicious PDF — malware analysis report

Static analysis result for SHA-256 f919b91382560b9d…

MALICIOUS

PDF

125.6 KB Created: 2021-09-03 02:36:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 8009dd6a0362347ccbeb2a91882a96ad SHA-1: 681f12f2432e728839fb0d404025da010af7c4e7 SHA-256: f919b91382560b9d300527262543a6cbf469809a61111e4004d88fd300ce668a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as 'Pdf.Phishing.Trojan'. The presence of numerous external URIs, including links hosted on compromised WordPress sites and disposable domains, indicates a link farm designed to redirect users. While no scripts were explicitly extracted, the nature of the heuristics suggests a phishing or redirection attempt, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9969

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/89d420cbc5065fc6efb20057d75f793d/40712955056.pdf In PDF document text
    • http://harasim.cz/uploaded/files/50948165789.pdfIn PDF document text
    • http://www.musicmaestrodiscos.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160b45527f24d8---98409001953.pdfIn PDF document text
    • http://villaturri.it/wp-content/plugins/formcraft/file-upload/server/content/files/160828699bd213---rijesamoteram.pdfIn PDF document text
    • http://geology.ie/wp-content/plugins/formcraft/file-upload/server/content/files/1609b8c4654632---gawajolutuburagete.pdfIn PDF document text
    • http://maxbrio.kr/files/files/51998141294.pdfIn PDF document text
    • http://africanhairbraidingsalon.com/userfiles/file/65938509640.pdfIn PDF document text
    • http://www.sudaff.com/pics/file/68077678162.pdfIn PDF document text
    • http://dent-pro.cz/pic/file/fobofidujoke.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609862671fd7f---gedotixeb.pdfIn PDF document text
    • https://sainaudit.mn/File/42216125926.pdfIn PDF document text
    • https://nnkcreations.com/userfiles/file/45174007847.pdfIn PDF document text
    • https://agrachoff.ru/wp-content/plugins/super-forms/uploads/php/files/c012a98a122a9b831d6e42290c2eca5d/83861256247.pdfIn PDF document text
    • https://www.northamericatalk.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609831d2f0a05---dokenekukefi.pdfIn PDF document text
    • http://kondicionery-dolgoprudny.ru/upload_picture/file/lafemujivinotel.pdfIn PDF document text
    • https://bonpetsupply.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f0cfb7c88a---71430675417.pdfIn PDF document text
    • http://www.medicalalliedtraining.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a358349730c---85654575118.pdfIn PDF document text
    • https://zzwgjx.com/d/files/96578902826.pdfIn PDF document text
    • http://hzjksj.com/images/upload/File/mexedebebizenopi.pdfIn PDF document text
    • https://aadhaarretail.com/administrator/imagetemp/file/dazasajeladibanidukaniror.pdfIn PDF document text
    • https://wacee.net/wp-content/plugins/formcraft/file-upload/server/content/files/1608cc49c7e4be---wozawufopokubotexeloxaguw.pdfIn PDF document text
    • http://centrons.com/uploaded/file/88647652060f0929d4755a.pdfIn PDF document text
    • https://loan-financial.com/wp-content/plugins/super-forms/uploads/php/files/c12a7cbc52c8c55627628e936c54df59/gireferilafosezuzulo.pdfIn PDF document text
    • http://automsystem.com/UploadFile/file/20210715174650954.pdfIn PDF document text
    • https://samyenngochoang.com/wp-content/plugins/super-forms/uploads/php/files/t14p0dg540ueu4cdbk8ckoksvd/gowavitupos.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=heber+carvalho+economia+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_off00017d76.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17D76 22556 bytes
SHA-256: 28111d2b181a0b5191e5a904d10571efe1822c4cc912b9b06a6fb4b30d59deb1
font_01_sfnt_off0001b699.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1B699 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001ceb0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1CEB0 10816 bytes
SHA-256: 378c85eb83a456f28d5a345f3e2f52fbb9e840c5855c3d777843e30ca8217f53