Malicious PDF — malware analysis report

Static analysis result for SHA-256 dbdb0b5ad646ec32…

MALICIOUS

PDF

71.3 KB Created: 2021-09-24 03:35:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: f549e4af3a6bb5b09c802e89c1e18bcd SHA-1: d19fd7c1b9cd3faea54952d96a5c5fc15a58b04d SHA-256: dbdb0b5ad646ec32ac18ee71e4b218387cdd176af51d707c4cc056c7fee4b2d1
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external URLs, some hosted on compromised CMS uploads. The presence of numerous URLs, including 'tiny+thief+download' in one, suggests an attempt to distribute malware or phish for credentials.

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 https://infrive.ru/uplcv?utm_term=tiny+thief+download PDF link annotation
    • http://mweb.cz/images/file/63490867715.pdfIn PDF document text
    • https://hirurgija.me/files/geliwani.pdfIn PDF document text
    • http://pro-roubenky.cz/UserFiles/File/robidoperokonemaxuzizela.pdfIn PDF document text
    • https://brusroom.com/wp-content/plugins/super-forms/uploads/php/files/e466cb300d1769ca38b708f84b112ee2/kukikerekurazakiwibup.pdfIn PDF document text
    • https://esperanzadeavila.com/fotos/file/rovupibopexaselo.pdfIn PDF document text
    • http://kengosushionlineorder.com/uploads/files/tapoki.pdfIn PDF document text
    • http://www.heatandgas.com/EditorImages/file/76177173559.pdfIn PDF document text
    • http://universalthailand.com/images/uploads/ckfinder/files/19792076924.pdfIn PDF document text
    • http://ucg-eg.com/userfiles/file/lejupe.pdfIn PDF document text
    • http://kamennykoberec.eu/editor_uploads/system/files/movatufewani.pdfIn PDF document text
    • http://southportrubbish.com/wp-content/plugins/formcraft/file-upload/server/content/files/161332afe36d10---dupuwinifeluzuledagu.pdfIn PDF document text
    • https://www.highettmetal.com.au/application/third_party/ckfinder/userfiles/files/lafir.pdfIn PDF document text
    • http://chretkinia.pl/userfiles/file/56954221810.pdfIn PDF document text
    • http://giasuthanhdat.vn/Images_upload/files/2998637237.pdfIn PDF document text
    • https://basalyemek.com/ckfinder/userfiles/files/48585402638.pdfIn PDF document text
    • https://alutat.com/data/file/58845766581.pdfIn PDF document text
    • http://www.ausafrica.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1614d17beae92c---81572119794.pdfIn PDF document text
    • http://www.gunyagder.org.tr/wp-content/plugins/super-forms/uploads/php/files/d98mm3i4a93en3p2p24us4bev1/48250156965.pdfIn PDF document text
    • http://feldbach-tourismus.at/files/domonafutiraziriji.pdfIn PDF document text
    • http://tianfonmm.com/d/files/damevafumedalinesisu.pdfIn PDF document text
    • http://quesnelfoundation.ca/userfiles/file/48846555129.pdfIn PDF document text
    • https://tutorbolivia.com/userfiles/file/46904587755.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_off0000b718.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB718 16124 bytes
SHA-256: 83840156d8ec2c37e431f4f44b8de6b7fed5aabade02defab924c0faf885282f
font_01_sfnt_off0000e06d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE06D 10344 bytes
SHA-256: f9b2808fe533349de5ba5f67e730f74beb48c40814232fd6e3ac9b3849210aa0
font_02_sfnt_off0000f7c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7C5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1