Malicious PDF — malware analysis report

Static analysis result for SHA-256 85c1986e9975aa4c…

MALICIOUS

PDF

96.0 KB Created: 2021-06-29 04:42:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 29bf51e572ec710aa10f2c39f445d3e0 SHA-1: 636ff2f37ade2ad7e9c21d357e98680f9152e26e SHA-256: 85c1986e9975aa4cda91c28f0771264ec9efd3991ddea88a3402495e00a48889
96 Risk Score

Malware Insights

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

The PDF document was flagged by an ML classifier as malicious and contains numerous embedded URLs. Several of these URLs point to compromised WordPress sites, indicating a link farm designed to redirect users to potentially malicious content. The document body is heavily obfuscated and unreadable, providing no direct clues to its intent beyond the embedded links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9936

Heuristics 5

  • 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://akarchlight.com/wp-content/plugins/super-forms/uploads/php/files/e5b094933b0ae946313d132b7475225d/fekiturin.pdf In PDF document text
    • https://retentionstudentexperience.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608540047d3d4---54672934924.pdfIn PDF document text
    • https://perfecthospital.org/FCKeditor/file/giruvojomujixokez.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d97188bec2b---nozexeduvosav.pdfIn PDF document text
    • http://domholidays.com/userfiles/file/lojidodazagajotosepamafe.pdfIn PDF document text
    • https://www.msolartop.cz/wp-content/plugins/formcraft/file-upload/server/content/files/160af458bf3523---ruxapalusanamepibi.pdfIn PDF document text
    • https://nnkcreations.com/userfiles/file/34442554777.pdfIn PDF document text
    • https://elitteaccesorios.com/wp-content/plugins/super-forms/uploads/php/files/7rai17uom2go4p85l71trg6br5/barefilofuzijemafomoj.pdfIn PDF document text
    • https://schreinerheusi.de/wp-content/plugins/formcraft/file-upload/server/content/files/16082e4cb77a20---niduzosaborevu.pdfIn PDF document text
    • https://lion-trading.co.uk/wp-content/plugins/super-forms/uploads/php/files/7lid07lfjmspcdcj7ftspbao0s/29863796269.pdfIn PDF document text
    • http://www.css-jp.com/upfile/files/2021/06/08/26970571597.pdfIn PDF document text
    • http://makaifruits.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bcce5a30cd4---rirunekekejetasi.pdfIn PDF document text
    • https://arizonapoolcontractor.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b08faf741e1---tofapiwapinog.pdfIn PDF document text
    • http://kunas.lt/app/webroot/uploads/files/xudomademuzo.pdfIn PDF document text
    • https://sweetestspaparty.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4922d26610---46282945464.pdfIn PDF document text
    • http://www.fattyweng.com.sg/wp-content/plugins/formcraft/file-upload/server/content/files/1609ea2027eedb---pejalileba.pdfIn PDF document text
    • https://patc.fr/imagesfile/somenisejesujamasu.pdfIn PDF document text
    • http://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/2a2660e7264a5c6446b1cd7ded801a8e/62021100880.pdfIn PDF document text
    • https://aashianarealty.com/file/16145129441.pdfIn PDF document text
    • https://ebooksweb.net/files/file/44876618469.pdfIn PDF document text
    • https://mission4recruitment.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a5af3df0388---motomaporadina.pdfIn PDF document text
    • https://kodeac.com/wp-content/plugins/super-forms/uploads/php/files/oo322ul0d5dmq2m7ko6o9laa3e/pokigoto.pdfIn PDF document text
    • http://vitanova-cattery.com/upload/file/45278828087.pdfIn PDF document text
    • https://genesislighting.net/wp-content/plugins/super-forms/uploads/php/files/05bf96aed283a8bf5380588a443c0ec5/sakewokudi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=testing+resume+for+4+years+experiencePDF 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_off0001144d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1144D 16952 bytes
SHA-256: 184547ba734e411ac6d2cd71e72f8fb4654d2f2d48da6f7f569393dc1646a179
font_01_sfnt_off00014091.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14091 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000158a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x158A8 11136 bytes
SHA-256: e362fd99d474f79b0dc9aa660eb47ceebe2bb1f7ee66002810276c3ac70a829e