Malicious PDF — malware analysis report

Static analysis result for SHA-256 1a9d42d4521459c5…

MALICIOUS

PDF

80.7 KB Created: 2021-09-06 00:09:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 872a45e33a3feb0bcd8db234ed92e531 SHA-1: 3bf08e4301f0d2571d140591621027830db0408e SHA-256: 1a9d42d4521459c520813d6e143c48d4463fb223df843f4526ebd7aaded83b36
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The file was detected as a malicious PDF by ClamAV and an ML classifier. It contains numerous links to external websites, many hosted on compromised WordPress sites, suggesting a link farm or phishing attempt. The presence of embedded URLs and the nature of the heuristics indicate that this PDF is designed to redirect users to potentially malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.immiflex.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131f1f971964---21013994488.pdf
    • http://www.nbrownies.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16077d005802a5---guwogodewo.pdf
    • http://clinicacomciencia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160ee10150802d---96167915078.pdf
    • https://dailyiat.com/html_upload/file/zijimijerujukexusit.pdf
    • http://www.dfdtrading.sk/ckfinder/userfiles/files/63407362424.pdf
    • https://btegypt.com/file/66989583624.pdf
    • http://www.kocay.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160c99f3f08d10---81232062679.pdf
    • http://mitcostruttori.it/userfiles/files/93053266576.pdf
    • http://teraval.cz/res/file/38813651576.pdf
    • http://accurateverdicts.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ae643bb0ffb---34782411340.pdf
    • https://mebelpozakazu.ru/wp-content/plugins/super-forms/uploads/php/files/41f5cf45459f50cab575a351f17b3ec8/13059252176.pdf
    • http://malabarisproducoes.com/arquivos/files/pazumeripagogeziwizudufi.pdf
    • http://fresh-j.info/images/uploadedimages/file/2175499383.pdf
    • https://xn--80aaa1arbfjoe3bzh.xn--p1ai/data/files/58590620341.pdf
    • http://comlark.ru/userfiles/files/66535182118.pdf
    • http://admio.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160a85ca815c04---satujizirakozorozor.pdf
    • https://certifiedmoversinc.com/wp-content/plugins/super-forms/uploads/php/files/356da64b7432e90690138419ef8ee7ab/fukudate.pdf
    • http://www.combatsim.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1607eb9a132fe0---33212655234.pdf
    • https://xn----7sbabak5acz7byau.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/8a5d4b2eb5e19bceb773d9873d6b15b8/40960878868.pdf
    • http://www.expo-hotel.com/english/wp-content/plugins/formcraft/file-upload/server/content/files/160a60d6876de6---xerixabenuzib.pdf
    • http://sunjewelsonline.com/userfiles/file/novujapujariromimemaguj.pdf
    • https://radekslodkiewicz.pl/files/file/43462850759.pdf
    • https://abctranslink.com/ckfinder/userfiles/files/balariwibegisezonewenu.pdf
    • http://oneself.pro/wp-content/plugins/formcraft/file-upload/server/content/files/160e60057d3848---63119060631.pdf
    • http://xn--12cbg9dihj7egda2g6a7dceb1d2cp4nvgf4f.com/datas/files/32175809800.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=cell+biology+pdf+notes
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d783.bin
a49b1fd2e40acedacacf52ad02ead88fe25f5e8e98a78b0afd247968f6e428c5
pdf-font-stream PDF embedded font (sfnt) at offset 0xD783 10696 bytes
font_01_sfnt_off0000efc9.bin
155f8c59a8485e840a1b9488666b6da643015601caf9214321effad11750452e
pdf-font-stream PDF embedded font (sfnt) at offset 0xEFC9 17700 bytes
font_02_sfnt_off00011d8a.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11D8A 16792 bytes