Malicious PDF — malware analysis report

Static analysis result for SHA-256 980f578a440f8e0d…

MALICIOUS

PDF

77.3 KB Created: 2021-09-16 00:43:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: f7f1e940b2eae216c90702564401ce75 SHA-1: d0f852e00c42d03665a910e26985a4905dee9066 SHA-256: 980f578a440f8e0d44681ebf0540e25dfbd676d7f17f1200be2c19deeb1c344d
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, with heuristics indicating it functions as a link farm. Several extracted URLs point to compromised CMS upload directories or disposable hosting, suggesting a phishing or malware distribution scheme. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, providing no direct user-facing content but containing numerous embedded URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://wtmasonry.com/ckfinder/userfiles/files/81688677020.pdf In PDF document text
    • http://jinwoosmc.com/userfiles/file/fomiguruzinabe.pdfIn PDF document text
    • https://www.thecandystoresudbury.com/wp-content/plugins/super-forms/uploads/php/files/ttkkg8p3mrtg76ba4dr942380h/sifegaxokodiwikidilakavo.pdfIn PDF document text
    • http://sfalojistik.com/userfiles/file/begij.pdfIn PDF document text
    • http://www.laterveer-biesenbeek.nl/ckfinder/userfiles/files/46514583668.pdfIn PDF document text
    • http://richardchong.com/userfiles/files/wanodevefipufas.pdfIn PDF document text
    • http://nineslash.com/user_file/file/13369693690.pdfIn PDF document text
    • https://jerseyshorepirates.com/userfiles/files/sudomuxubituwezosifef.pdfIn PDF document text
    • http://destockbaby.com/ckfinder/userfiles/files/figewalumiserozidawo.pdfIn PDF document text
    • https://webmenuplus.com/images/file/funovetuta.pdfIn PDF document text
    • http://kino-cosmik.ru/sadm_files/gimoxijibowor.pdfIn PDF document text
    • https://karate2.cdmedia.pl/userfiles/file/4305728335.pdfIn PDF document text
    • https://www.mds-horizons.com/upload/files/33298061866.pdfIn PDF document text
    • https://bimetoor.com/basefile/bimetoorir/files/4877348338.pdfIn PDF document text
    • https://www.toptalentusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613730c0a6a2e---27224479681.pdfIn PDF document text
    • https://nabsangram.com/userfiles/file/9774531553.pdfIn PDF document text
    • http://sun-green.be/ckfinder/userfiles/files/jisopiso.pdfIn PDF document text
    • http://avatars.ru/userfiles/file/pinitimedizemux.pdfIn PDF document text
    • http://mouaumfb.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613799a173c63---1518331426.pdfIn PDF document text
    • http://kechengchem.com/upload/files/suluxo.pdfIn PDF document text
    • http://kwiatmetal.pl/userfiles/file/10897686644.pdfIn PDF document text
    • https://xn--80apefbdm9ah5g.xn--p1ai/userfiles/rejasofivifodigen.pdfIn PDF document text
    • https://claphamjunction.com.au/wp-content/plugins/super-forms/uploads/php/files/9e6526d6ba4e013d09164325f2bb4b98/64810147504.pdfIn PDF document text
    • http://baigeleather.com/userfiles/file/64423793439.pdfIn PDF document text
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614178b4481c4---fujogag.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=ffbe+bahamut+guidePDF 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_off0000c711.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC711 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000df23.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF23 18604 bytes
SHA-256: 5799a106b52650784adeba7c99a127b61cda5c92cfa3a43ad137b3293ff8ab68
font_02_sfnt_off00010fd4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FD4 10480 bytes
SHA-256: 359c15f558c5033c4fb480bdc7462055403516f30822de9e04fdb4cf912fe861