Malicious PDF — malware analysis report

Static analysis result for SHA-256 8b8d647bf70dfbb5…

MALICIOUS

PDF

74.4 KB Created: 2021-09-04 06:20:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 1afd28e9ebeae7148068958e331827fd SHA-1: bfb65be64cbd2fd291d09a8dcd0dbdc7e6012312 SHA-256: 8b8d647bf70dfbb52c2a9068771d7adf9f2d902795bfecc711e2b158f7ac9343
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a large number of embedded URLs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly support its malicious nature. No scripts were extracted, but the URL structure and heuristic firings are sufficient to determine the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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 http://ufnk.fr/app/webroot/files/file/12589908788.pdf In PDF document text
    • http://indexone.ru/upload/file/bufawadorijozufopetagikob.pdfIn PDF document text
    • http://myapartment.de/web/editor/files/62175444508.pdfIn PDF document text
    • http://studiogiovannone.com/userfiles/files/gifenavasodoxaniwalijuv.pdfIn PDF document text
    • https://anakmeong.com/contents//files/bitakubebesivizofoz.pdfIn PDF document text
    • https://ensasoft.com.tr/wp-content/plugins/super-forms/uploads/php/files/38ur047orrsq9ns9038n5h0v1f/gupelizavowor.pdfIn PDF document text
    • http://www.chicagoalphas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160de32f701884---wujax.pdfIn PDF document text
    • https://rebates.forex/wp-content/plugins/super-forms/uploads/php/files/1mcihcc8j1urdqess7vmjlujj0/67125285994.pdfIn PDF document text
    • http://world-housing.jp/ckfinder/userfiles/files/dudupixatemapijekudo.pdfIn PDF document text
    • http://principessavencanice.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084b1b8db146---52986832404.pdfIn PDF document text
    • http://sugarfree-gelato.com/upload/file/lutotezijexubimexa.pdfIn PDF document text
    • https://cristiandellavedova.com/wp-content/plugins/super-forms/uploads/php/files/fdl5mkg6721vo4ip6n7k4da545/67550100409.pdfIn PDF document text
    • https://www.alertgy.com/wp-content/plugins/super-forms/uploads/php/files/bdc4c1c472eeb70253da3ff015a9b7ca/25348719373.pdfIn PDF document text
    • https://mma-montessori.com/admin/ckfinder/userfiles/files/tenepidevamog.pdfIn PDF document text
    • https://intelean.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074f9f921c74---35224819001.pdfIn PDF document text
    • http://lotuscourtpune.com/wp-content/plugins/super-forms/uploads/php/files/ks22cqfeugtg5cnu8hkap555j1/gopigowupetemop.pdfIn PDF document text
    • http://olympusflights.com/files/files/70114807491.pdfIn PDF document text
    • http://zonwering-nederland.com/ckfinder/userfiles/files/sodanojuwisapamimipopasot.pdfIn PDF document text
    • http://sbs-group.co/userfiles/files/ruxujo.pdfIn PDF document text
    • http://fotofolliasanlazzaro.it/userfiles/files/38014187983.pdfIn PDF document text
    • http://daegyung.kr/userfiles/file/20210828211404.pdfIn PDF document text
    • https://arerp.kr/data/file///kurafajawomumod.pdfIn PDF document text
    • http://allg-gyn.ch/userfiles/file/defuvusumezabazatarar.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=unitary+method+worksheet+pdf+for+class+8PDF 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_off0000bb8f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBB8F 17500 bytes
SHA-256: 5704069031b650dc682dabfadd22c574d3496ca0bf79c01f755978e6c3120ff7
font_01_sfnt_off0000e90c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE90C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010123.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10123 11392 bytes
SHA-256: 348e70518a7d12880884323a43305947ffca9e6ab040c7c0df568bb1f2e72256