Malicious PDF — malware analysis report

Static analysis result for SHA-256 aa052d99498261a8…

MALICIOUS

PDF

84.8 KB Created: 2021-06-28 04:53:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 1ae00756ab4a1b86d15303bc32d69c2d SHA-1: 06408aaa8e86f4b12dca735051c26a8eb4d7560d SHA-256: aa052d99498261a89432637ef0b672eba9f0ba5c71679ee67fa04322c6ecd7aa
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a phishing or trojan threat. It contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable domains, suggesting a link farm designed to redirect users to malicious content. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, further obscuring its true intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9860

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://decoveinvestment.com/userfiles/file/23716963861.pdf In PDF document text
    • http://mountcalvary76.com/clients/9/90/9062e1c9f2360b2cedac6e2854879500/File/11165357547.pdfIn PDF document text
    • http://grandinhr.eu/images/user/file/bonufikap.pdfIn PDF document text
    • http://gingerbreadvillage.org/clients/e/e3/e396b250b60561adcb946853f9f62e29/File/bofekalemuligidojumut.pdfIn PDF document text
    • https://www.sanier.pl/wp-content/plugins/super-forms/uploads/php/files/9gmi6viplumbtc010tme0hqqml/94228354021.pdfIn PDF document text
    • https://camile.vn/wp-content/plugins/super-forms/uploads/php/files/rogqn7qgr3ocmq17kog4lfnhro/nivofakol.pdfIn PDF document text
    • http://plenar.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160d0b09a9ddbc---62731769270.pdfIn PDF document text
    • http://www.x454.com/wp-content/plugins/super-forms/uploads/php/files/49npe394cnq6icf84r9728ntr5/divipotezofalukapuvor.pdfIn PDF document text
    • https://noithatkuongthinh.com/uploads/files/99636926109.pdfIn PDF document text
    • http://sanphamhanquocymy.com/uploads/files/98965852098.pdfIn PDF document text
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/sibutmgl55p7gpsmu58p6ip670/pidekorirokabunebunemodav.pdfIn PDF document text
    • http://www.inhd.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c217a71094e---1054570139.pdfIn PDF document text
    • https://www.budgetskemaet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160a8a183202cf---vumelo.pdfIn PDF document text
    • http://lideparts.com/userfiles/file/1620765969.pdfIn PDF document text
    • http://www.hgbehringer.de/img/files/files/4272758123.pdfIn PDF document text
    • http://ateliergermain.net/sites/default/files/file/60601613758.pdfIn PDF document text
    • http://poltinik.ru/userfiles/file/98199239573.pdfIn PDF document text
    • http://www.miamiairportlimo.net/wp-content/plugins/formcraft/file-upload/server/content/files/160d7e5f4e80c4---28651528246.pdfIn PDF document text
    • https://www.rockandroll.blog.br/wp-content/plugins/super-forms/uploads/php/files/qtbki61uc78623sf64imcmjkjo/lutepojowekoxiluteku.pdfIn PDF document text
    • https://petroblend.com/wp-content/plugins/formcraft/file-upload/server/content/files/160796c3206494---dijagesenefejolipolavozi.pdfIn PDF document text
    • https://www.helpagesl.org/wp-content/plugins/formcraft/file-upload/server/content/files/1609ed7ab40a68---42607346682.pdfIn PDF document text
    • https://www.auditek.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160c9c3129a823---52489753632.pdfIn PDF document text
    • https://radmangroup-ye.com/rgfiles/file/disisubalupedenexi.pdfIn PDF document text
    • http://www.carolglassman.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608802f2119ce---78476737882.pdfIn PDF document text
    • https://www.verpoort-bouw.be/wp-content/plugins/formcraft/file-upload/server/content/files/1607e8855e35fd---58534451693.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=get+in+the+way+example+sentencePDF link annotation
    • https://sharpspringwww.kinsta.cloud/wp-content/plugins/super-forms/uploads/php/files/25c7417793800ef829ace4c7075bbc7e/bonipifofoz.pdfIn PDF document text
    • 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_off0000e9f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9F8 16584 bytes
SHA-256: ec16313899738135fc4e5b38fff3679a5d14bbebdbc7abc534593553dff36a18
font_01_sfnt_off000114f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114F7 10760 bytes
SHA-256: 8e84cac4ac219694890afc1d54ea28fba7d3f5c6ae0448525e605791466ea3c5
font_02_sfnt_off00012d9d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D9D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1