Malicious PDF — malware analysis report

Static analysis result for SHA-256 57381927ad1bd700…

MALICIOUS

PDF

84.9 KB Created: 2021-06-29 06:12:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-15
MD5: 961a50b15ba4e26dd16ff82dfbcdec34 SHA-1: 2820fb67b3bf17af059344c2530ddbe37a4b262b SHA-256: 57381927ad1bd7002889756ad8579a714b44766169fd4ec687542a5bc5745990
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF document identified as malicious by ML classifiers and ClamAV. It functions as a link farm, containing numerous URLs pointing to compromised WordPress upload directories. These links likely serve as a distribution mechanism for further malicious content, aligning with a phishing or malware distribution attack pattern. No scripts were extracted, but the PDF structure and URL patterns suggest an attempt to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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://www.bluegreenshouseboats.in/wp-content/plugins/formcraft/file-upload/server/content/files/160d7c48610724---debijijeguwa.pdf In PDF document text
    • http://joshuadacosta.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b1e5b9e4e59---lujuxobenezovutogotirur.pdfIn PDF document text
    • http://dancingstarsgreenwich.net/clients/1/10/10f73e4104fe6082999c9b722aa65ba2/File/wabesunatu.pdfIn PDF document text
    • https://homeaestheticsllc.com/wp-content/plugins/super-forms/uploads/php/files/e189f6775e6558d9fe47d76b4f6b3c3d/vufolatifevobafi.pdfIn PDF document text
    • https://cornerstonelaw.eu/userfiles//file/65093907413.pdfIn PDF document text
    • https://myupfield.link/wp-content/plugins/super-forms/uploads/php/files/1ruuhski86o1o0tm40ok7kureg/32971590152.pdfIn PDF document text
    • https://www.dyna-tech.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1606d8d16d26e1---52948019918.pdfIn PDF document text
    • http://flightshop.jp/images/blog//file/6779399537.pdfIn PDF document text
    • http://www.akutrans.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cb88456812f---50961452981.pdfIn PDF document text
    • https://senzedigicraft.com/wp-content/plugins/super-forms/uploads/php/files/5c77a19398a33cca0817205960e77bc9/86790408597.pdfIn PDF document text
    • https://www.nordatec.com/wp-content/plugins/super-forms/uploads/php/files/2n7ug943gvq47c2bdmr2qu23gt/dewuwe.pdfIn PDF document text
    • http://nuyewpilot.academy/wp-content/plugins/super-forms/uploads/php/files/74930dc62f7615a79d995bfcc79002e9/digeg.pdfIn PDF document text
    • http://timatey.kz/wp-content/plugins/super-forms/uploads/php/files/q5vgp6ihl09lc9unsqrrv88sj6/vigiz.pdfIn PDF document text
    • http://www.rify.us/cms-uploads/files/xipabavojor.pdfIn PDF document text
    • https://www.certificagreen.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8b767bd0de---24670680874.pdfIn PDF document text
    • http://aberdeeneyes.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607b9e4b78c36---pavove.pdfIn PDF document text
    • http://www.etoiles-recrutement.com/wp-content/plugins/formcraft/file-upload/server/content/files/160782354706fc---11630863539.pdfIn PDF document text
    • http://bahattinburyan.com/userfiles/file/68137914787.pdfIn PDF document text
    • http://sieckultury.pl/wp-content/plugins/super-forms/uploads/php/files/59498f51d4c5f070b956b0a2d76bc06e/28617042411.pdfIn PDF document text
    • https://www.inter-tube.co.uk/wp-content/plugins/super-forms/uploads/php/files/50a5800d88cee4b9a35318239c1addc5/72201017016.pdfIn PDF document text
    • https://webhostmurah.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d4fd9b472c7---rizusosejinemiruv.pdfIn PDF document text
    • http://friluftsgruppen.se/wp-content/plugins/formcraft/file-upload/server/content/files/160c58eb453c56---sagavubeviveruwidepiro.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=auto+answer+app+for+androidPDF 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_off0000ea58.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA58 10612 bytes
SHA-256: ebf7cef90c14c855e8404c56f345ebd62e3832a898ad00765c54f1b50b1b76b8
font_01_sfnt_off000102d8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102D8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011aea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11AEA 16808 bytes
SHA-256: 3a210fa40db79dee4d538b2eda9c29901e9878942170e032480c860a12373f70