Malicious PDF — malware analysis report

Static analysis result for SHA-256 840a51f7e507637b…

MALICIOUS

PDF

111.9 KB Created: 2021-07-05 21:48:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 075858edf71c66ce35dea07329c2e06d SHA-1: 54a3ab7ba4b13e133e7a476d6e10f7373bd86cb8 SHA-256: 840a51f7e507637ba2fc0cc316c783106a5334f609473976945bd62ab64731a5
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised WordPress upload directories and other disposable hosting, indicating a link farm designed to redirect users to malicious sites. The ML classifier and ClamAV detection strongly suggest this PDF is malicious, likely serving as a phishing lure or a distribution point for further malware. No scripts were extracted, but the structure and URL patterns are indicative of a phishing or content-luring attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9330

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://amrapalispot.com/userfiles/file/78273984819.pdf In PDF document text
    • http://www.canadavisaservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608fce33539a9---nevubularuvarex.pdfIn PDF document text
    • http://www.opencalgary.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a5ff1044864---51521031921.pdfIn PDF document text
    • https://seataclightingalaska.com/wp-content/plugins/super-forms/uploads/php/files/2c8e26a954f9e8703bc71a10fc223a04/tofuze.pdfIn PDF document text
    • https://djhelaly.com/wp-content/plugins/super-forms/uploads/php/files/fe5dabdea11ca14b733d6f2d6b635358/7365867026.pdfIn PDF document text
    • http://cukiernia-waltar.pl/qcms/userfiles/file/87394225391.pdfIn PDF document text
    • http://grandbarnettfamily.com/clients/a/a0/a01b80d98e57c38af56892ab55e7d82f/File/72861878793.pdfIn PDF document text
    • http://tv-kitchen.ru/files/files/rojobi.pdfIn PDF document text
    • http://xn--80aafbkbafwdti1ahihccrg.xn--p1ai/pict/file/lujubotatalokozuf.pdfIn PDF document text
    • http://ziepniekkalns.lv/wp-content/plugins/formcraft/file-upload/server/content/files/160718edb207e0---34773582130.pdfIn PDF document text
    • https://seerupit.dk/assens/file/tanij.pdfIn PDF document text
    • http://kstarsmall.net/userfiles/file///88644632757.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160731fa743e38---tasixopavipof.pdfIn PDF document text
    • https://travels-ukraine.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a85554aa406---lowetosozivanisulawuzuf.pdfIn PDF document text
    • http://viaterrestre.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16073edfe73a22---28479342245.pdfIn PDF document text
    • http://22743333.com/userfiles/files/9352564754.pdfIn PDF document text
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/3420b2c03dde9db9f188d87e576fb479/sifojibofinuxukikidi.pdfIn PDF document text
    • https://amartzon.store/wp-content/plugins/super-forms/uploads/php/files/c46c4f993b84d2c80aaf3ee5823c4e68/64834844709.pdfIn PDF document text
    • https://sketchup360.vn/wp-content/plugins/super-forms/uploads/php/files/879h4s32vp4v5e94ptimu8rjsp/32846823194.pdfIn PDF document text
    • http://repare-ton-smartphone.com/userfiles/file/67338225982.pdfIn PDF document text
    • https://action-roofing.com/wp-content/plugins/super-forms/uploads/php/files/2807b7db304cb35bd71b4637c98b7540/53252283449.pdfIn PDF document text
    • https://charlesstreetvideo.com/userfiles/file/nozorirojifuxusuwegubojof.pdfIn PDF document text
    • https://xn--80aaijzh9b.xn--90ae/documents/file/funekajaki.pdfIn PDF document text
    • http://boeschfamilytravels.com/clients/43210/File/6552911356.pdfIn PDF document text
    • https://careersourceokaloosawalton.com/files/public/11586127004.pdfIn PDF document text
    • http://loaamtran.vn/files/usersfiles/files/42593655736.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=accosted+meaning+in+englishPDF 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 5

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010a00.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A00 26176 bytes
SHA-256: 91808cfbf49601e8de8b905d7b0f27c41a552ab2642bb5d47a67c6405892cf77
font_01_sfnt_off00014a12.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14A12 10700 bytes
SHA-256: 2bad2ec984fda1376059e6d4b7401afff6315fdbf55fa62d07e2317ebc5660c6
font_02_sfnt_off0001622a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1622A 4324 bytes
SHA-256: 2224a6617c2c3a66e3963dfd5c4556b657edbba011ebaf37f273cf6638409131
font_03_sfnt_off000171dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x171DD 20856 bytes
SHA-256: c5be44c91a877128288df7c8dacbc9767847eda7e090a665328fb6f2af67ac67
font_04_sfnt_off0001974d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1974D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1