Malicious PDF — malware analysis report

Static analysis result for SHA-256 b018f1846d16fb56…

MALICIOUS

PDF

83.5 KB Created: 2021-09-18 07:01:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 43c681742bde9f577b08532f80b1d689 SHA-1: 5d6c6e62f12f7ae645283eda3ba1210f12948554 SHA-256: b018f1846d16fb5669a68fd892cfca67b063216021cefd5378de2c7995ebfae5
156 Risk Score

Malware Insights

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

The file is identified as malicious by ClamAV and an ML classifier. It contains multiple URLs pointing to compromised WordPress sites and other disposable hosting, indicating a link farm designed to redirect users. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' confirms this behavior, suggesting the document's primary purpose is to drive traffic to these malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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 http://viaterrestre.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161406b7f1e48a---28445479698.pdf In PDF document text
    • https://anzhero-sudzhensk.verlauf-ekb.ru/admin/ckfinder/userfiles/files/68213566928.pdfIn PDF document text
    • http://flex-link.cn/uploadfiles/files/lusuxifipipanowupoko.pdfIn PDF document text
    • http://7seapharmtech.com/Uploadfiles/files/muxotane.pdfIn PDF document text
    • https://vadihosting.com/calisma2/files/uploads/65025902903.pdfIn PDF document text
    • http://www.mab-solutions.fr/upload/file/21727303702.pdfIn PDF document text
    • http://cmrivestimenti.com/userfiles/files/tisezusuk.pdfIn PDF document text
    • http://gotoippc.com/ckfinder/userfiles/files/josasoturedesisetev.pdfIn PDF document text
    • http://immobiliareborghi.com/userfiles/files/bawoporu.pdfIn PDF document text
    • https://la-klamm.org/Files/files/zikasimaxafuxaratimuraf.pdfIn PDF document text
    • http://rdmsrl.it/userfiles/files/57881470283.pdfIn PDF document text
    • http://winhazel.com/indigo/ckfinder/userfiles/files/wikefavuxewozofipisowexid.pdfIn PDF document text
    • http://www.advancedevents.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613c36798f9fe---konebomewuvawibutuweroj.pdfIn PDF document text
    • http://artetendasud.it/userfiles/files/11380716570.pdfIn PDF document text
    • https://stockbauer.hu/uploads/file/derika.pdfIn PDF document text
    • https://evrenmentese.com/upload/ckfinder/files/42574715298.pdfIn PDF document text
    • https://heks-tech.com/app/webroot/userfiles/files/pikunajijitasaba.pdfIn PDF document text
    • https://chulintemple.house-well.com/CKEdit/upload/files/26446343626.pdfIn PDF document text
    • https://www.hasmow.com.au/application/third_party/ckfinder/userfiles/files/41269436936.pdfIn PDF document text
    • http://goang-hann.com/uploads/files/202109120347252955.pdfIn PDF document text
    • http://isspskola.lv/userfiles/files/makuzejevisilozijonivofu.pdfIn PDF document text
    • https://listapp.in/ci/userfiles/files/29054659461.pdfIn PDF document text
    • http://gangwonbnb.com/FileData/ckfinder/files/20210918_5ACA228230570FF5.pdfIn PDF document text
    • https://mkting.com.co/wp-content/plugins/super-forms/uploads/php/files/3f500bc7a684181882e7ca0c4243d52e/tineriziza.pdfIn PDF document text
    • https://egokituz.org/files/galeria/files/90377483526.pdfIn PDF document text
    • http://gearonlaw.net/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/menujas.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=the+extent+to+which+in+a+sentencePDF 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_off0000e092.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE092 18508 bytes
SHA-256: cde386d8087683a2ca41d6b22c5a9707967655f3ffae933e9686c4c7d0fee26f
font_01_sfnt_off0001106a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1106A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012881.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12881 10332 bytes
SHA-256: f26fb2398a53d87658bf0c6d725a1f54ec54411003af9404d603f1d82caf622f