Malicious PDF — malware analysis report

Static analysis result for SHA-256 a36c3dd915390313…

MALICIOUS

PDF

70.1 KB Created: 2021-09-16 06:33:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: a5f63e668de04f5d7d8eb2773e0332d0 SHA-1: 43b70deabf8ca4f6a58b9529facfa7e1bfdb3cea SHA-256: a36c3dd915390313f15fdf43b6a6b0dee9b0f0e6272b9cdd6d16b7595c262dc8
156 Risk Score

Malware Insights

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

The file is a PDF identified by ClamAV as 'Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0'. Heuristics indicate it functions as a link farm, with multiple embedded URLs pointing to potentially compromised or disposable hosting. The ML classifier also strongly flagged this PDF as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://snf.styleguides.ch/userfiles/files/29731610140.pdf In PDF document text
    • http://islaminkiel.de/webmisr/uploadwebmisr/file/zesavovivopatalisuvaj.pdfIn PDF document text
    • http://rund-sro.cz/UserFiles/File/sinovamulemomomijavadili.pdfIn PDF document text
    • https://mywayrtk.com/userfiles/file/20648486823.pdfIn PDF document text
    • https://kuraniterbiye.com/resimler/files/21363650124.pdfIn PDF document text
    • http://plenaseguroseprevidencia.com/fotosempresa/files/kagovodenexosesav.pdfIn PDF document text
    • https://optimuselearningschool.com/learning/site/images/uploadfiles/45447445256.pdfIn PDF document text
    • https://photopoligrafic.ru/ckfinder/userfiles/files/fikejupezag.pdfIn PDF document text
    • http://freeski.hu/freeski/file/74474277697.pdfIn PDF document text
    • http://camberwelltaxi.com/survey/userfiles/files/40831959148.pdfIn PDF document text
    • https://bfull.ru/uploads/files/70942584514.pdfIn PDF document text
    • http://www.1atlanticfunding.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613aaac85a668---kinekuwokefuxupamijopoxo.pdfIn PDF document text
    • https://tecnicadovolante.com/images/file/47075532642.pdfIn PDF document text
    • https://pui-vital.ro/msg_media/file/99586678135.pdfIn PDF document text
    • https://kenkochaya.com/user_data/ckfinder/files/fuvisuva.pdfIn PDF document text
    • https://sanruouvang.net/images/uploaded/file/begeja.pdfIn PDF document text
    • http://richmediahouse.com/admin/uploads/file/82260337629.pdfIn PDF document text
    • https://lakeshoresmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/dus9pp6j3n0or215597knt2c01/84327431507.pdfIn PDF document text
    • https://www.physioaktivkramer.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613dcc8710f25---66838389129.pdfIn PDF document text
    • http://stoka-saarlouis.de/userfiles/file/17265473095.pdfIn PDF document text
    • http://blgjad.com/upload/files/51490986929.pdfIn PDF document text
    • http://www.stadion-zarya.ru/ckfinder/userfiles/files/2926470004.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=catecismo+para+primera+comunion+pdfPDF link annotation
    • http://s292376414.onlinehome.fr/datas/imgmail/file/87788059006.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_off0000b168.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB168 15872 bytes
SHA-256: 862e8309a42da1ce3b1f3bc99ad203094ae5d535824b07a8f9177fe1bfb1d1bd
font_01_sfnt_off0000d994.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD994 10864 bytes
SHA-256: eb0321d99d73d9e5b81b6eb6e44a6dadd69ca3554281151a373096d6898283b4
font_02_sfnt_off0000f2ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2AB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1