Malicious PDF — malware analysis report

Static analysis result for SHA-256 8851163937b71da9…

MALICIOUS

PDF

93.8 KB Created: 2021-08-12 20:51:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: f0cc56e5e0c9bc257cd70a3e6499251e SHA-1: bae88046e92112e7a324716f9f81a9aa79e81264 SHA-256: 8851163937b71da9de5ade9144669306dfb11e6281fe17097d2a5687327b6dfc
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier indicated a high probability of maliciousness. The document contains numerous links pointing to compromised WordPress upload storage and disposable hosting, suggesting it functions as a link farm to distribute malicious content or phish for information. No scripts were extracted, but the structure and URL analysis strongly indicate a malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

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://themodernla.com/wp-content/plugins/super-forms/uploads/php/files/fde9553683d5c7ce51362e1352eef97b/teteraruti.pdf In PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c685381c0f---88010816028.pdfIn PDF document text
    • https://guapa2.com/admin/fck/file/53521988876.pdfIn PDF document text
    • http://salt17.com/userfiles/files/pamuwowodawemubiroxa.pdfIn PDF document text
    • http://texinpack.com/uploadfile/file///2021080604451343.pdfIn PDF document text
    • http://greenbrier101.com/userimages/kuzudemoj.pdfIn PDF document text
    • https://saftanton.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160c7a5ff3bcd5---80730471092.pdfIn PDF document text
    • http://tuzvedo.hu/elemek/file/warumixuladedu.pdfIn PDF document text
    • http://cristalensi.com/public/File/56555331882.pdfIn PDF document text
    • https://dgssu.com/upfolder/e/files/20210704091926.pdfIn PDF document text
    • http://msamerica.net/clients/873634/File/28249868001.pdfIn PDF document text
    • http://sinara.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/16080fed58989c---rufoxes.pdfIn PDF document text
    • http://www.opencalgary.org/wp-content/plugins/formcraft/file-upload/server/content/files/1606cca60228a1---38608288427.pdfIn PDF document text
    • https://www.olympusnorge.no/wp-content/plugins/super-forms/uploads/php/files/jmjluma8iq8f4u6e7vr0ibmld8/83739739624.pdfIn PDF document text
    • http://in-dapt.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a07c1556c3---pezorojidesusu.pdfIn PDF document text
    • https://xn----9sbccjdbca7cyaieg1a3j.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/eabcd9ff7173677895dfd18b28645243/80885958416.pdfIn PDF document text
    • http://kartywspomnien.pl/uploads/assets/file/tajotobitozakine.pdfIn PDF document text
    • http://mountmedpharmacy.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1606d43d4340ae---vatogapirobiwilosimenepi.pdfIn PDF document text
    • https://stagerightstaging.com/wp-content/plugins/super-forms/uploads/php/files/de007386e585e234c32ee3f1ab33edde/25098694740.pdfIn PDF document text
    • http://comicpapyrus.com/wp-content/plugins/super-forms/uploads/php/files/e798b4ec0a98706fcded6b8d308a7e67/jewuboporerobabivalolobi.pdfIn PDF document text
    • https://esteticarcare.com/wp-content/plugins/super-forms/uploads/php/files/1da16eda650f51a0a2c3e5c15b1c2e64/sigoxomowikakogedidiparem.pdfIn PDF document text
    • https://www.hamburgeriaagricola.com/wp-content/plugins/super-forms/uploads/php/files/q3lv2od2otsvo3oq0licf3m2p1/39530088805.pdfIn PDF document text
    • http://nuyewpilot.academy/wp-content/plugins/super-forms/uploads/php/files/ad2385ef0d061f345eeb02281bd4c912/41543099715.pdfIn PDF document text
    • http://ansatrans.ru/admin/ckfinder/userfiles/files/pavabizalubadizofinug.pdfIn PDF document text
    • http://www.birapart.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b19a3fd11fc---wizuwefigonavorus.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=marshall+football+plane+crash+victimsPDF 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_off000109b5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109B5 16956 bytes
SHA-256: ff6e4645441167c06f97cef7d71a766d47b31a4b70c05490c5c8496d9c079a55
font_01_sfnt_off00013617.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13617 10944 bytes
SHA-256: ab333576f815f0b33efa9f4691c8ccb83a6a3decdd85cb2091e03cb084ca950f
font_02_sfnt_off00014f10.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14F10 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1