Malicious PDF — malware analysis report

Static analysis result for SHA-256 d9161416d840aa0d…

MALICIOUS

PDF

76.6 KB Created: 2021-07-27 18:20:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 3d8a37e607c01133e916489e0a981488 SHA-1: faa153ce8fb5760356cf72d103d34f99332576e7 SHA-256: d9161416d840aa0d61fd91d2d398d529b27f7dae63a4313fe90482041cb23ed8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, with heuristics indicating it functions as a link farm hosted on compromised CMS uploads. The document body is heavily obfuscated and contains no readable text, but the presence of numerous URLs pointing to potentially compromised sites suggests a phishing or redirection attempt. No scripts were extracted, but the PDF structure itself is leveraged to host these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9893

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://patriot.ch/wp-content/plugins/super-forms/uploads/php/files/pke9noqos46bqcjo4q0v2m6gor/kafutalobexulovagasaku.pdf In PDF document text
    • http://cu-hinothai.com/ckfinder/userfiles/files/44206819243.pdfIn PDF document text
    • https://www.lipfish.no/wp-content/plugins/formcraft/file-upload/server/content/files/160a2c8272f2f4---85564928186.pdfIn PDF document text
    • http://christembassydocklands.org/wp-content/plugins/super-forms/uploads/php/files/a56f078375043bd71a4bbae0545db191/18638675224.pdfIn PDF document text
    • https://www.thecandystoresudbury.com/wp-content/plugins/super-forms/uploads/php/files/8hifjuj5q11ctepmav65kv7co3/17638110115.pdfIn PDF document text
    • http://xedaptap.net/userfiles/file/99507325084.pdfIn PDF document text
    • http://www.bestlifepolicy.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160f5a2eac66e5---sivibokosidope.pdfIn PDF document text
    • https://parklanehotel.asia/userfiles/file/torizesojagunekurobox.pdfIn PDF document text
    • http://millecolori.it/images/file/nibetukemep.pdfIn PDF document text
    • http://olneyjune65.com/clients/d/dc/dcef5d22f85ec69f5810ba62c2e8cf46/File/bamosonebuzifato.pdfIn PDF document text
    • http://puppies-4u.com/clients/e/e7/e7f09595da74c05d2059c741134300d2/File/58597776947.pdfIn PDF document text
    • https://esterkins.de/ckfinder/userfiles/files/98594783216.pdfIn PDF document text
    • http://xn----8sbpvg0afdbe.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/uh2dupnd8s8ab1m1vlt0fq15l3/nugafejowenuronaj.pdfIn PDF document text
    • https://aawyx.com/sites/default/imageuser/file/fijisisadom.pdfIn PDF document text
    • http://vincityhomes.vn/wp-content/plugins/super-forms/uploads/php/files/f2g81smll6b9oavsphqgvr5g11/subonubewikusovi.pdfIn PDF document text
    • http://specimport.by/files/files/77990849778.pdfIn PDF document text
    • https://www.rogierstoel.nl/wp-content/plugins/super-forms/uploads/php/files/6shum96v8c1h7vklfnuustqsq3/gopegowiji.pdfIn PDF document text
    • http://yasaitogo.com/uploads/files/xadizovaxokugoluwamojug.pdfIn PDF document text
    • https://trucraftsmanship.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab4db71dbf7---jilawatexikokig.pdfIn PDF document text
    • http://klubalfa.org/img/userfiles/file/26277106275.pdfIn PDF document text
    • http://www.combatsim.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1609a8233c22a0---87531597237.pdfIn PDF document text
    • http://biosite.ru/images/news/file/gudiridufomezese.pdfIn PDF document text
    • http://asu.com.vn/wp-content/plugins/super-forms/uploads/php/files/gobdo1je1je1kff6i06vs8mnsr/wowotili.pdfIn PDF document text
    • https://orkhaconstruction.com/wp-content/plugins/super-forms/uploads/php/files/l9o0skvjh61vhmsenqoia78bt0/73383216324.pdfIn PDF document text
    • http://netinflux.net/userfiles/file/zepodepakakudagujoven.pdfIn PDF document text
    • https://coloreverything.love/wp-content/plugins/super-forms/uploads/php/files/b4450bbee8315bee488dc70225dd11d1/32362396740.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=maravilloso+desastre+pel%C3%ADcula+repartoPDF 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_off0000c61e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC61E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000de30.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE30 17272 bytes
SHA-256: bba2337d7dc8f1b1d01d6a11eaae908b2b21976f5c2480d637b802df7ad6bd67
font_02_sfnt_off00010a57.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A57 10624 bytes
SHA-256: dce2d6d41bdb35acc428a3bd3912b2559fc568911efc60850cdf61b3fdba1960