Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f7aa368dbaf3735…

MALICIOUS

PDF

86.8 KB Created: 2021-06-27 13:28:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 5533ddf4679daa9ac4b8e99b128eaed7 SHA-1: 90867f721edf630cdf8d723f884967918ec59356 SHA-256: 8f7aa368dbaf373513b84faed30a3e7fe34d5c557afdf5b4fb88b42427da3bbe
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, directing users to numerous external URLs, some hosted on compromised CMS platforms. The primary purpose appears to be redirecting users to potentially malicious content or for SEO manipulation, rather than direct exploitation within the PDF itself.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://motelandratecuci.ro/userfiles/file/91294099404.pdf In PDF document text
    • http://kaowei.tw/image/files/20210605_090356.pdfIn PDF document text
    • http://sattamatkapatti.com/userfiles/file/45980505073.pdfIn PDF document text
    • https://telewebmarketing.com/FCKeditor/file/logoruxisuzepuwagan.pdfIn PDF document text
    • https://firsatoyun.com/calisma2/files/uploads/voredakutodomosorapabe.pdfIn PDF document text
    • http://rgn2u.com/userfiles/files/kafijo.pdfIn PDF document text
    • https://www.femregenx.co.za/wp-content/plugins/super-forms/uploads/php/files/u2vlpuogmd60p5eppb9rrepi48/tazub.pdfIn PDF document text
    • http://www.norestim.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160a365807d648---45244027970.pdfIn PDF document text
    • http://witnesstherealist.com/wp-content/plugins/super-forms/uploads/php/files/73016169911ded5b9754edd1f56d84ad/96156634628.pdfIn PDF document text
    • http://oinworkshop.com/clients/6/6d/6d9161a7191ba42f41383a85782e2f4f/File/78775449358.pdfIn PDF document text
    • http://akicgiyim.com/userfiles/file/1694871116.pdfIn PDF document text
    • http://grani-tonkogo-mira.ru/wp-content/plugins/super-forms/uploads/php/files/2fb35c91558e9efbde1b123b734b2168/roxeb.pdfIn PDF document text
    • http://www.klpreschool.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607aa09b1cb38---20058309082.pdfIn PDF document text
    • https://forumhotel.by/wp-content/plugins/super-forms/uploads/php/files/4qf4ql4gc93ejt7bmhahfkkr86/viwivodenaribajemekifeped.pdfIn PDF document text
    • https://www.accidentinjuryalbuquerque.com/wp-content/plugins/super-forms/uploads/php/files/2dte1ualt01tlovemjhlb5rqbj/52376104324.pdfIn PDF document text
    • https://3dreamvr.com/wp-content/plugins/super-forms/uploads/php/files/903296f6b40c6d7dea28cba01cbc9cf4/55980129747.pdfIn PDF document text
    • http://bogelaipigeon.com/upload/file/zumalobow.pdfIn PDF document text
    • https://vuaship.com/wp-content/plugins/super-forms/uploads/php/files/nru0unthoei3kh8ghbobaol8h8/14146760148.pdfIn PDF document text
    • http://vaughanreunion.com/clients/7/7c/7cfe0b8ff6d5e3136a6575a9b258a09c/File/gudulekezurutepurubub.pdfIn PDF document text
    • http://ozanatalan.com/iboard/includes/userfiles/files/wuzetumemi.pdfIn PDF document text
    • http://bmsorganica.com/userfiles/file/zojukajepabusirixoj.pdfIn PDF document text
    • http://allycatering.com/userfiles/sutesokupegazutawapiwux.pdfIn PDF document text
    • http://wojno-stal.pl/pliki/file/nimokufi.pdfIn PDF document text
    • https://psychologgia.pl/Upload/file/fapilidebotaxilak.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=diary+of+a+wimpy+kid+full+movie+free+onlinePDF 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_off0000f0f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0F1 16964 bytes
SHA-256: 3cd1c5969b4b3c4e2dd596ed6b5424579a02cfea97a0aef17e09b23a0b289f20
font_01_sfnt_off00011cae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CAE 10852 bytes
SHA-256: 64da67d2fb0cc4711709bdc3ae040a00c2810a0499c48f20b814ef39e9590a66
font_02_sfnt_off000135bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x135BF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1