Malicious PDF — malware analysis report

Static analysis result for SHA-256 16415ed7d02f0d24…

MALICIOUS

PDF

90.0 KB Created: 2021-07-31 14:38:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-01
MD5: e455b8c9eff34649a967a1b2ea7a3ead SHA-1: 1770fa7cc26196c5ef162ac90a94c57a92883338 SHA-256: 16415ed7d02f0d24d446eff796eb12ee972a9b9b912f83acd37a81d7273674a1
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. It uses a callback-phone (TOAD) lure. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9876

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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://brmc.jp/user_data/userfiles/files/juwoxepamanipoxa.pdf In PDF document text
    • http://lsbwg.com/ckfinder/userfiles/files/20210713/1721304509.pdfIn PDF document text
    • https://carstenrath.com/wp-content/plugins/super-forms/uploads/php/files/p02nopp7kqrb0dltubvpkfoqnf/kujilojut.pdfIn PDF document text
    • http://thankschicken.com/uploads/files/vazunadumegozatexu.pdfIn PDF document text
    • https://www.lowdoc-loans.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160831e59c43e3---risewidewomub.pdfIn PDF document text
    • http://palami.by/images/file/gobepubodipixafofi.pdfIn PDF document text
    • https://cruiseship.cruises/wp-content/plugins/super-forms/uploads/php/files/fir8j6u11d3tftr6sfiopcfc9n/xemaburevumug.pdfIn PDF document text
    • https://mytopics.it/uploads/file/84851626065.pdfIn PDF document text
    • http://northwestpixie-bobs.com/clients/e/e1/e1941a3904c49320334fd90e0ed9e852/File/semovadori.pdfIn PDF document text
    • https://accesoriosalmayor.com/images/userfiles/file/67315570955.pdfIn PDF document text
    • http://massageindex.nl/images/uploads/36208676730.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160768570218af---8347952108.pdfIn PDF document text
    • http://7tec.ru/userfiles/files/lasidaseziziwinedigefowin.pdfIn PDF document text
    • https://www.peeryhotel.com/wp-content/plugins/super-forms/uploads/php/files/52cd78b784b621febc1f39d681010aa1/69605842814.pdfIn PDF document text
    • https://www.fecomerciomg.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607d3cd163981---wefowigetiwoju.pdfIn PDF document text
    • https://perfecthospitals.com/FCKeditor/file/vizitag.pdfIn PDF document text
    • https://readxyz.org/wp-content/plugins/super-forms/uploads/php/files/0146f73db255680037f2429fb8a25e39/44496757942.pdfIn PDF document text
    • https://intelean.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c9f69deb958---xukizufozipu.pdfIn PDF document text
    • http://dashoernerboot.de/userfiles/dexekikipokek.pdfIn PDF document text
    • http://multifamilyfoundation.org/clients/3/38/38c33163524538bb895552046de0b362/File/8172966509.pdfIn PDF document text
    • http://www.airportlimofortlauderdale.net/wp-content/plugins/formcraft/file-upload/server/content/files/160c0d8d5587a9---39190759679.pdfIn PDF document text
    • http://conservationenergy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a5656f44d00---1257307047.pdfIn PDF document text
    • http://we2meeting.com/ckfinder/userfiles/publics/files/mabivi.pdfIn PDF document text
    • https://fobiy.net/wp-content/plugins/super-forms/uploads/php/files/9e07d44591bd4dfe325d715a95df1c7d/42329412856.pdfIn PDF document text
    • https://anmimar.com/royal/userfiles/file/manaxamabafojepirof.pdfIn PDF document text
    • http://argentum.com/wp-content/plugins/super-forms/uploads/php/files/l14m073bsf6dfpelpmogcbdl78/8730332010.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=how+do+i+turn+off+wifi+calling+on+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_off0000faf2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAF2 17408 bytes
SHA-256: a1c58ff991bc2083cd695550f350ee902c9359c4ccc04f5af5d2858f726cd1a8
font_01_sfnt_off000128cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x128CB 10528 bytes
SHA-256: 002ed8d35dfd188047a6cbae2d63bfe02680d8ec20b8caf05e3b1cc629063034
font_02_sfnt_off000140ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x140AB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1