Malicious PDF — malware analysis report

Static analysis result for SHA-256 b047a478e7522e96…

MALICIOUS

PDF

108.9 KB Created: 2021-08-18 04:41:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: af3c2bba997abe3fc34ce0985f29951d SHA-1: 52cbebce77609fb5bef9a9651c5956aa009b7935 SHA-256: b047a478e7522e9676148b3aaa28b435ffda42af287fae9e576abc5c000f03e4
156 Risk Score

Malware Insights

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

The file was identified as malicious by a machine learning classifier and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to compromised WordPress sites and disposable domains, likely to lure users to phishing or malware distribution sites. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, suggesting a tactic to improve search engine ranking for malicious content.

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://cructi.ru/uplcv?utm_term=worksheet+1+the+carbon+cycle+answer+key PDF link annotation
    • http://www.drop-lok.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a691619547---71018976455.pdfIn PDF document text
    • https://cmetrix.net/ckfinder/userfiles/files/pozesivafa.pdfIn PDF document text
    • http://www.urbanwaterways.info/files/54950838470.pdfIn PDF document text
    • http://graphicon.hu/wp-content/plugins/formcraft/file-upload/server/content/files/1606c968cdd802---vurixadavagopipugo.pdfIn PDF document text
    • http://0-50.ru/userfiles/file/wovuliruwepigesene.pdfIn PDF document text
    • http://ebiocell.com/uploadfile/file///2021071304515918.pdfIn PDF document text
    • https://trichynext.com/wp-content/plugins/super-forms/uploads/php/files/25eb98ce4c1c8f3dd78cd76fc189acff/89518261746.pdfIn PDF document text
    • http://www.whirlpool-beachcomber.at/wp-content/plugins/formcraft/file-upload/server/content/files/160f1a6598e5fa---20396004643.pdfIn PDF document text
    • https://taiwan-tiaya.com/upload/tiaya_official/files/zadenuxopunamubefuso.pdfIn PDF document text
    • http://pensionpoint.cz/userfiles/files/bafaburipu.pdfIn PDF document text
    • http://tikatalog.sk/_files/file/butenujupulusifozatizire.pdfIn PDF document text
    • https://suma.ca/upload/editor/file/fefubuvikelo.pdfIn PDF document text
    • https://churchofgodinjamaica.org/app/webroot/files/sivawoxopun.pdfIn PDF document text
    • https://isabellepieman.com/userfiles/file/torolomobetukubotexelibo.pdfIn PDF document text
    • http://ilsogno-bomboniere.com/userfiles/files/gagirilifibo.pdfIn PDF document text
    • http://retroldn.com/userfiles/file/70893817730.pdfIn PDF document text
    • http://ayurveda-shiatsu-nice.com/upload/files/2220806354.pdfIn PDF document text
    • http://namkhoabacninh.com/images/files/ruxewuvi.pdfIn PDF document text
    • http://boulderdivorcelaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160875f0f8debf---94138457948.pdfIn PDF document text
    • http://tomlitkom.ru/ckfinder/userfiles/files/vasorikilisajubelevovoxo.pdfIn PDF document text
    • https://xn--interpeas-r6a.es/upload/files/16789428880.pdfIn PDF document text
    • https://aihr-iadh.org/uploads/FCK_files/file/zavus.pdfIn PDF document text
    • https://yourtuscanyguide.com/wp-content/plugins/super-forms/uploads/php/files/uc7qa0virv55iket15qk1817k2/kidokukixezipox.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_off0001452a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1452A 10712 bytes
SHA-256: 0a90666e5ee6ffee8bfd068740a161fad99299254f24c99511b4da59c7e20370
font_01_sfnt_off00015dec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15DEC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000175fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x175FE 18196 bytes
SHA-256: f5c4a28e8a357cca5949586a30e7a9b5d81dc2e45ae3a42b8686017fdcceb054