Malicious PDF — malware analysis report

Static analysis result for SHA-256 0c17ac9d75670ca0…

MALICIOUS

PDF

96.0 KB Created: 2021-09-15 16:46:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: fd2f3dc06f3f3bf01b766f6012037bb0 SHA-1: 1bd4a85efcbb292120e3d333a6dd3aebf11d2b71 SHA-256: 0c17ac9d75670ca0041ec3ee6d8a1c4cba9d009fabe68c6653e0cf7a1ab9fa4e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was identified as malicious by ClamAV and an ML classifier. It contains numerous embedded URLs, many of which point to compromised WordPress upload storage or disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The heuristic PDF_SEO_DISPOSABLE_LINK_FARM indicates a pattern of small PDFs used as link farms on disposable hosting, further supporting the phishing or malware distribution intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://irlanc.ru/uplcv?utm_term=sine+amplitude+and+period PDF link annotation
    • http://naim.naparts.com/images/fck/file/38736909965.pdfIn PDF document text
    • https://evocative.ru/wp-content/plugins/formcraft/file-upload/server/content/files/161411bc104b23---jisulu.pdfIn PDF document text
    • http://kovove-ploty-brany-zabradli.cz/UserFiles/File/99884257744.pdfIn PDF document text
    • http://mq-water.net/upload/vofelefabagu.pdfIn PDF document text
    • http://nasledie-sluck.by/var/upload/file/10376337645.pdfIn PDF document text
    • http://thietbimaugiao.vn/Images_upload/files/60534250376.pdfIn PDF document text
    • https://cafemocion.com/userfiles/file/40977388174.pdfIn PDF document text
    • http://homeopathyhongkong.org/files/98268550791.pdfIn PDF document text
    • http://beiwendq.com/data/attachment/file/26680642092.pdfIn PDF document text
    • http://alconsprom.ru/ckfinder/userfiles/files/fibatakowexaxekimavibi.pdfIn PDF document text
    • http://pnalog.ru/images/file/44297625895.pdfIn PDF document text
    • http://www.ashtralmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140f490da6c4---89249723788.pdfIn PDF document text
    • http://rabotatver.ru/userfiles/admin/weraliroje.pdfIn PDF document text
    • http://fkhd.cz/data/img/50328517741.pdfIn PDF document text
    • http://yibetter.com/data/files/xefotiwenijejepefe.pdfIn PDF document text
    • http://asr-net.ru/uploads/files/91680577456.pdfIn PDF document text
    • http://hvezda-pardubice.cz/files/file/79175877039.pdfIn PDF document text
    • http://vinhthuanvietnam.com/upload/files/dotefuvi.pdfIn PDF document text
    • https://lanhcongnghiepthinhphat.com/upload/files/wisawe.pdfIn PDF document text
    • https://lifeteacher.tw/uploads/files/202109120557499557.pdfIn PDF document text
    • http://mycoapaisyl.com/webimages/files/vusenizudurupulot.pdfIn PDF document text
    • https://www.lenoir-elec.com/wp-content/plugins/super-forms/uploads/php/files/p5uno6o6n3129j58diqilon1gd/33804816941.pdfIn PDF document text
    • https://www.euroservicemilano.it/wp-content/plugins/formcraft/file-upload/server/content/files/16135aced52cbf---95759316322.pdfIn PDF document text
    • https://stockbauer.hu/uploads/file/84942814941.pdfIn 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/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_off00011154.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11154 10560 bytes
SHA-256: a0dc3c9a94e93466e837526ca7f712845daff523e26b329445f0a7288048daec
font_01_sfnt_off00012951.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12951 18700 bytes
SHA-256: 03ea63c98700aa444d9b503aa7f00d14e60ed7ef9766dea82baa73763fdcb71e
font_02_sfnt_off00015a40.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15A40 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1