Malicious PDF — malware analysis report

Static analysis result for SHA-256 4f768be8feeca801…

MALICIOUS

PDF

71.0 KB Created: 2021-09-15 11:55:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: d9d35c121ccd5ed01777e59a10162049 SHA-1: ebd6097b7388c2b508c0964d047f8d7b1f3d4b43 SHA-256: 4f768be8feeca801074245de30367ac777de17f6add487c4756886690719aa0a
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Several heuristics indicate the PDF functions as a link farm, with many URLs pointing to potentially compromised or disposable hosting, suggesting an attempt to redirect users to malicious sites. The presence of numerous unknown URLs supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://www.puhito.hu/uploads/kilimujomenazuranajuru.pdf In PDF document text
    • https://takarasushimn.com/userfiles/files/76624873776.pdfIn PDF document text
    • http://yuilchem.com/userData/board/file/39715218517.pdfIn PDF document text
    • https://gulertrafik.com/wp-content/plugins/super-forms/uploads/php/files/ssg5f2dbvhfutaqre36gpri5qk/52411074218.pdfIn PDF document text
    • http://viorina-deko.com/images/file/18881168591.pdfIn PDF document text
    • https://daulte.ch/ckfinder/userfiles/files/28200720445.pdfIn PDF document text
    • http://driver-jazda.pl/upload/file/17372145172.pdfIn PDF document text
    • http://hkwwta.org/userfiles/kowad.pdfIn PDF document text
    • https://aljuboori.com/userfiles/files/pexoxekezetezen.pdfIn PDF document text
    • http://border-collie.ru/sites/default/files/file/vozukepagawirokofaxamo.pdfIn PDF document text
    • http://yousefmaktabi.com/ckfinder/userfiles/files/73271334870.pdfIn PDF document text
    • http://gearcon-eng.com/file_media/file_image/file/41540362000.pdfIn PDF document text
    • https://tiklatakip.com/calisma2/files/uploads/19683652081.pdfIn PDF document text
    • https://etravelbox.com/scgtest/team-explore/uploads/files/lapiwef.pdfIn PDF document text
    • http://rothemtour.com/FileData/ckfinder/files/20210904_77844A33A10A7696.pdfIn PDF document text
    • http://amghanoi.com/images/ckeditor/files/30908217157.pdfIn PDF document text
    • http://azizavacanze.com/userfiles/files/mofotajibife.pdfIn PDF document text
    • http://www.niceresidence.net/image/upload/File/37097896424.pdfIn PDF document text
    • http://nuyewrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/070fdf6c6e4bf7961bbc29ea872e6bd7/34351326358.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/16139f50791ee6---56301416325.pdfIn PDF document text
    • http://wsmr.us/userfiles/file/dumelel.pdfIn PDF document text
    • http://aexpress.lv/index/images/up/file/78407863317.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=square+root+numbersPDF 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_off0000b3f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB3F8 16408 bytes
SHA-256: 0f470b01872a3aa509df004bec82a9ba22e8ec83ded6f1d05688d789043b64a3
font_01_sfnt_off0000de57.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE57 10592 bytes
SHA-256: 4d5f4617e2ea035cadfaab7579e490247e27a35c5791c5a31725d5c57e8e371a
font_02_sfnt_off0000f68b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF68B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1