Malicious PDF — malware analysis report

Static analysis result for SHA-256 73d6e442d7b196da…

MALICIOUS

PDF

85.6 KB Created: 2021-09-10 20:37:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: f5d0947adcf75ae5e1878c579d3ff201 SHA-1: 6c142aa5d18331219b4ab9210c6aebb987637695 SHA-256: 73d6e442d7b196da3301fdbbef3004a98e179b21e9aa8300d6a6991d884e808d
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many hosted on compromised CMS platforms or disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The document body is heavily obfuscated and unreadable, providing no direct content clues, but the heuristic firings are sufficient to infer the attack pattern.

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 http://studioingtassinari.eu/userfiles/files/lusasifo.pdf In PDF document text
    • http://vijyaiprismcrm.com/userfiles/files/rowajejuwasefutitedozikav.pdfIn PDF document text
    • http://tbeaindia.com/userfiles/file/33501010208.pdfIn PDF document text
    • https://www.penyembuhanholistikreiki.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613331fdc73b0---dapatodukivu.pdfIn PDF document text
    • http://audiencefertilization.com/fckeditor/editor/filemanager/connectors/php/userfiles/file/46056689626.pdfIn PDF document text
    • http://innotec-industrie.be/userfiles/file/53732381285.pdfIn PDF document text
    • https://goez1.com/10005001208290177/ckfinder/userfiles/files/10284837888.pdfIn PDF document text
    • https://dmddsgn.com/wp-content/plugins/super-forms/uploads/php/files/58a790bbf058da85a9a2d4e9f0da2f1d/xalujigizexi.pdfIn PDF document text
    • http://champaigncursillo.com/userfiles/file/99803861345.pdfIn PDF document text
    • https://cupanghitam.com/contents/files/11619062492.pdfIn PDF document text
    • https://gaseg.com/wp-content/plugins/super-forms/uploads/php/files/ke384e8nglo8bcgvuga2ebs449/peluweserajugaw.pdfIn PDF document text
    • http://turatabor.hu/media/lodurezefiru.pdfIn PDF document text
    • https://amigo-shop.105h.net/upload/files/nokejivediruw.pdfIn PDF document text
    • http://johnlillylaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/kozorusi.pdfIn PDF document text
    • http://www.yourhealthyourchoice.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613aaf5c7b574---72899199061.pdfIn PDF document text
    • http://xn----otbbfbbknchz.xn--p1ai/sadm_files/ralopomutiwa.pdfIn PDF document text
    • http://lexen.ca/userfiles/files/88816356217.pdfIn PDF document text
    • https://digireg.at/upload/legupemosebavugi.pdfIn PDF document text
    • https://next-engineering.com/userfiles/files/53760829832.pdfIn PDF document text
    • http://thienthaopc.com/upload/FCK/file/48611761200.pdfIn PDF document text
    • https://lakecountyoralsurgery.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134452384f29---27889076815.pdfIn PDF document text
    • http://nct-vn.com/userfiles/file/vimenotevidopav.pdfIn PDF document text
    • https://suemsas.com/wp-content/plugins/super-forms/uploads/php/files/p14fgobp69u0s3adok226n05v0/19352579937.pdfIn PDF document text
    • https://bbu.vn/Images_upload/files/43527558995.pdfIn PDF document text
    • http://naturestuff.nl/siteimages/file/32522007318.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=use+yet+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_off0000ecca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECCA 17468 bytes
SHA-256: 8e4a6026d502b5ebbd904397030ca4ce63ec9295d148a152644491e01e4731c8
font_01_sfnt_off000119e2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x119E2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000131f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x131F9 10076 bytes
SHA-256: 8516a330ffb40d4edffd4a47c4d0dfbc3f3d07411f9969a28b5475c6e95867ac