Malicious PDF — malware analysis report

Static analysis result for SHA-256 16a8b708d8867029…

MALICIOUS

PDF

82.1 KB Created: 2021-09-03 18:11:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: b9b547ade491c6fa2c797f51963db64f SHA-1: f9632c6717f4dab51508d010a55e394b9e6bc9d7 SHA-256: 16a8b708d88670299b956d2334fd777bc5de6e44e00dbb4c78535bcb8ee90f63
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan payload. It functions as a link farm, with numerous embedded URLs pointing to compromised CMS uploads and disposable hosting, likely to distribute further malware or phish for credentials. The use of multiple compromised and disposable domains suggests an attempt to evade detection and maintain operational resilience.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://www.unicodesystems.com/wp-content/plugins/super-forms/uploads/php/files/c5gqp34p12rmuqt2pbim73ftk1/kiwojamit.pdf In PDF document text
    • http://makesomenoise.hu/upload/file/tadezalitiv.pdfIn PDF document text
    • http://nicenpos.com/userData/board/file/74175092170.pdfIn PDF document text
    • http://gentlemensquartersbarbershop.com/wp-content/plugins/super-forms/uploads/php/files/ca7947b825df87e077fbe09cd78bc751/59581797742.pdfIn PDF document text
    • http://quick-thailand.com/images/uploads/file/pagilopo.pdfIn PDF document text
    • https://nam.it/wp-content/plugins/formcraft/file-upload/server/content/files/1612fb9ad63d2e---mujizo.pdfIn PDF document text
    • https://profix.fr/ckfinder/userfiles/files/totixexawurifapirufozurar.pdfIn PDF document text
    • http://tfh-filter.hu/_user/file/98946483813.pdfIn PDF document text
    • https://bursakaynak.com/userfiles/file/24977603540.pdfIn PDF document text
    • http://computerdoki.hu/user/file/zurovixuko.pdfIn PDF document text
    • http://chagatea.ru/wp-content/plugins/super-forms/uploads/php/files/be39d9ac5fdab8bf49c5054bddf2fc0a/podelidabebujobi.pdfIn PDF document text
    • http://fecirturizm.com/resimler/files/8841582707.pdfIn PDF document text
    • https://sidexsideaudio.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e6a470655c---66461690116.pdfIn PDF document text
    • https://ipcare.nl/wp-content/plugins/super-forms/uploads/php/files/1vkgf3hjh8gcb25haocr2gaa1n/79554347982.pdfIn PDF document text
    • http://alltechsro.cz/files/48627934942.pdfIn PDF document text
    • http://piecco.eu/upload/files/37445557561.pdfIn PDF document text
    • https://masterok-kovka.ru/wp-content/plugins/super-forms/uploads/php/files/b7f83f057c42bf811c180742d3a10af1/3279161325.pdfIn PDF document text
    • http://whkmradio.com/userfiles/file/kilalogelowesokuvodumevov.pdfIn PDF document text
    • http://www.apsetedavisi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f1d5f9d4e7---59017527416.pdfIn PDF document text
    • http://mesotects.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a72b1770de6---38197853970.pdfIn PDF document text
    • http://ccforum.kr/uploads/file/1622219832.pdfIn PDF document text
    • http://www.lavalledesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a53886c4057---33806533507.pdfIn PDF document text
    • http://hosungtour.net/FileData/ckfinder/files/20210708_8AF2930A33D00451.pdfIn PDF document text
    • https://ebooksweb.net/files/file/konufirajusazorut.pdfIn PDF document text
    • http://burmeseburmilla-allevamento.com/userfiles/files/vegurexipolegavazufup.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=coordination+compounds+questions+pdfPDF 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_off0000db86.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB86 17632 bytes
SHA-256: d2ba2fe75262851d6ec668f52dbe7439eb081d846c42dff025237de800fa9bce
font_01_sfnt_off000108d4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108D4 11012 bytes
SHA-256: e4e5b994dd088672567dd926a30277d3f21ff541ca64be9f9b6b762aaaaa430d
font_02_sfnt_off0001223e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1223E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1