Malicious PDF — malware analysis report

Static analysis result for SHA-256 3537fa899954b829…

MALICIOUS

PDF

85.9 KB Created: 2021-08-22 03:04:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 17a0573f7efb6d953cb5bb52ad31be4e SHA-1: a9ed9ee67f2b5f4433d2d5c750dd4f5ca3d96453 SHA-256: 3537fa899954b829d6b03574f494d2f98c46ddbab10db45285f3bd633a418885
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier. It contains numerous links, many pointing to compromised WordPress upload directories and disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of these links indicates an attempt to lead users to phishing sites or download further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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 https://kund-in.com/userfiles/file/92636750966.pdf In PDF document text
    • http://jockmurray.com/wp-content/plugins/formcraft/file-upload/server/content/files/160918a7cd4309---61659953801.pdfIn PDF document text
    • http://olynskiconstruction.com/pics/file/pujun.pdfIn PDF document text
    • http://firesecurity.sk/userfiles/file/lisepafojozi.pdfIn PDF document text
    • https://hophamthaibinh.com/upload/files/texufiraxibisiverivikusuk.pdfIn PDF document text
    • https://www.lightingsolutionsal.com/wp-content/plugins/super-forms/uploads/php/files/70cc306d239e5f5d1dabc25ad6d6d99b/87351987574.pdfIn PDF document text
    • https://sdyh.gr/wp-content/plugins/super-forms/uploads/php/files/k2jc04dong8s7du6qepifha7m7/zuligebuva.pdfIn PDF document text
    • https://aadhaarretail.com/administrator/imagetemp/file/juwumiratatubiko.pdfIn PDF document text
    • https://impariant-club.ru/wp-content/plugins/super-forms/uploads/php/files/ad31a8dcd2e2c26810e7d9b986d5eaeb/fititumuwotu.pdfIn PDF document text
    • https://bhsbeacon.com/FCKeditor/file/85047522580.pdfIn PDF document text
    • https://nicemexico.net/wp-content/plugins/formcraft/file-upload/server/content/files/1609ee3ef6bc34---89249151750.pdfIn PDF document text
    • https://pisangmanis.com/contents//files/57975154496.pdfIn PDF document text
    • http://www.wallisandemmanuel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ec9f48aee7---50279673471.pdfIn PDF document text
    • http://apsara.ru/userfiles/file/44516432750.pdfIn PDF document text
    • https://www.elektrobetrieb-scholz.de/wp-content/plugins/formcraft/file-upload/server/content/files/160e45988a7c24---30114569789.pdfIn PDF document text
    • http://www.louisefarmersmith.com/admin/ckeditor/ckfinder/userfiles/files/79888340863.pdfIn PDF document text
    • http://www.moteco.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160e667c1d5d5c---tewerelasunela.pdfIn PDF document text
    • http://karpatskiles.ru/store/files/24894601244.pdfIn PDF document text
    • https://www.novet.de/wp-content/plugins/formcraft/file-upload/server/content/files/160dd74e84feec---83831070400.pdfIn PDF document text
    • http://www.thediethub.in/wp-content/plugins/formcraft/file-upload/server/content/files/160aeb56b464de---26348263535.pdfIn PDF document text
    • https://dmshospital.com/mm_engg/files/78177128250.pdfIn PDF document text
    • http://www.novosib-sport.ru/ckfinder/userfiles/files/tagaxufonixejig.pdfIn PDF document text
    • http://gptools.net/userfiles/file/23068321186.pdfIn PDF document text
    • https://petroblend.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c52439350ce---ravesofazemogep.pdfIn PDF document text
    • http://brilliantsolarpaneling.com/userfiles/file/67514121316.pdfIn PDF document text
    • http://eubeer.vn/uploads/files/18468612484.pdfIn PDF document text
    • https://acethamessecurity.co.uk/wp-content/plugins/super-forms/uploads/php/files/e585c48f8577e9e315f2819c2cee46a7/lafikud.pdfIn PDF document text
    • http://qianlong99.org/ckfinder/userfiles/files/18375085240.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=ciri+telur+ascaris+lumbricoidesPDF 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_off0000ed36.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED36 16548 bytes
SHA-256: d4a6500d9baef06323d93058aec2f982ad5e4946c75e5d231d947adf227f33fc
font_01_sfnt_off00011820.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11820 10700 bytes
SHA-256: 333a2b6f50e66d451ca067c3117c3aa06e8505db26add7987f815bb0cf537f77
font_02_sfnt_off000130bc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x130BC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1