Malicious PDF — malware analysis report

Static analysis result for SHA-256 d9a4e1cfae42404a…

MALICIOUS

PDF

79.6 KB Created: 2021-09-18 07:12:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 3f439c634d5df92c34ca5405940182a8 SHA-1: 28b096e8f91f2a8cb9b543a3b845a55d4a18ff44 SHA-256: d9a4e1cfae42404ab5f14690ac963d3d6cf224333dcaf0c6ac257f645b8fb37a
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as a phishing trojan and a machine learning classifier indicated a high probability of maliciousness. Several heuristics indicate the document functions as a link farm, directing users to potentially compromised websites or disposable hosting. The embedded URLs, such as http://lisahyatthealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b0824b6100---davex.pdf, are likely intended to host further malicious content or facilitate phishing attempts.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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.inhd.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613ba86ad9625---72797361917.pdf In PDF document text
    • https://groupunsur2.com/contents/files/vugabazowegebuk.pdfIn PDF document text
    • http://goldenstarhotel.vn/images/uploads/files/66887608836.pdfIn PDF document text
    • http://kochamsushi.pl/UserFiles/file/18766524008.pdfIn PDF document text
    • https://vayamcs.com/content_files/files/11407347206.pdfIn PDF document text
    • http://icmasistemas.com/userfiles/files/fawimuzizox.pdfIn PDF document text
    • http://pekingtogo.com/uploads/files/pupelewogajofadimuruxena.pdfIn PDF document text
    • https://afmiletisim.com/resimler/files/pulesafo.pdfIn PDF document text
    • https://primax.fr/wp-content/plugins/super-forms/uploads/php/files/bl8b50ik801smb0ib3im9pgja0/19552620588.pdfIn PDF document text
    • https://idealist.ro/userfiles/file/kenefababalapegi.pdfIn PDF document text
    • http://nhasachconggiao.com/luutru/files/24761997204.pdfIn PDF document text
    • http://sicompk.com/survey/userfiles/files/94580970408.pdfIn PDF document text
    • http://oa30us.com/userfiles/file/tiriwosagakidozewugiku.pdfIn PDF document text
    • http://wannawwannie.pl/userfiles/file/90217801246.pdfIn PDF document text
    • https://ojazzdance.fr/userfiles/file/vebajomoxo.pdfIn PDF document text
    • https://fa-vietnam.com/webroot/img/files/goforelo.pdfIn PDF document text
    • http://studiogallerani.it/userfiles/files/wonusewisi.pdfIn PDF document text
    • http://lisahyatthealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b0824b6100---davex.pdfIn PDF document text
    • https://33mobility.net/uploads/files/kuguxap.pdfIn PDF document text
    • https://gpuhub.net/wp-content/plugins/super-forms/uploads/php/files/cbp7701okjh4u76p5j09uju15a/kobuvinaxepapexudazazeg.pdfIn PDF document text
    • http://thanuyentea.com/ckfinder/userfiles/files/26869529914.pdfIn PDF document text
    • http://hengfengpaper.com/filespath/files/20210918110756.pdfIn PDF document text
    • http://hanilkwanla.com/uploads/files/5815360416.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=reasons+to+stay+alive+read+onlinePDF 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_off0000d53b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD53B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ed52.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED52 10464 bytes
SHA-256: 051bccd17d0a3dfc57c4b4bb5ff69bcb50bb58e7db5de12188d56fb0d604c7f9
font_02_sfnt_off0001053a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1053A 16772 bytes
SHA-256: a9408d04851da4c8637d5782a9d6c98192ad71036031ebc13d2850bba70ff274