Malicious PDF — malware analysis report

Static analysis result for SHA-256 91b4a68b1aa1be85…

MALICIOUS

PDF

93.9 KB Created: 2021-09-04 19:28:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 5fefa1a8bbc8746dc9b0d708e902b6a7 SHA-1: 23c254f6f738abeffeec36dca705a5f53d9dcaff SHA-256: 91b4a68b1aa1be853687165b8ef4dbb208ba735a03a5e8429b3166dfa66cdcd3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous URLs, many of which point to compromised WordPress sites or disposable hosting, suggesting it functions as a link farm. The presence of embedded URLs and the nature of the links indicate an attempt to redirect users to malicious content, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://crewmak.ru/uplcv?utm_term=der+aufbau+des+organismus+pdf PDF link annotation
    • http://bochosushi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607cfd637b151---lukepetorirutolidewegumi.pdfIn PDF document text
    • https://flavio-tonon.it/public/file/5258745563.pdfIn PDF document text
    • https://franchise-vietnam.com/app/webroot/img/files/72598417035.pdfIn PDF document text
    • http://shangrilayunnan.com/ckfinder/userfiles/files/mawinijakimumajupepu.pdfIn PDF document text
    • https://abzesolar.com/uploads/files/14605467263.pdfIn PDF document text
    • http://compie.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160beb93c3416e---25672186466.pdfIn PDF document text
    • https://www.crossfitparamaribo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160dbe011aca4a---5343120186.pdfIn PDF document text
    • https://trucraftsmanship.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607360567f4e2---kufomigiwizibisuwakoxoz.pdfIn PDF document text
    • https://alasclub.gr/neuro/ckfinder/userfiles/files/lowafabiwiwunopigixi.pdfIn PDF document text
    • https://www.lashharmony.co.uk/wp-content/plugins/super-forms/uploads/php/files/rpbmc8cv2iqa7m9239spvcpsjk/gibagagunisofaxekule.pdfIn PDF document text
    • http://www.qookspot.kitchen/wp-content/plugins/formcraft/file-upload/server/content/files/16110d7bd19f39---pivaxevawogoza.pdfIn PDF document text
    • https://osiindia.org/ckfinder/userfiles/files/14091063529.pdfIn PDF document text
    • https://lcd96.ru/wp-content/plugins/super-forms/uploads/php/files/dff734f79c3311934a3baabde97068a0/8175218177.pdfIn PDF document text
    • https://www.dolphinrfid.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607bf9331e4a2---wedolonupaga.pdfIn PDF document text
    • https://autoteam.in/ckfinder/userfiles/files/wuwefimibibaxojij.pdfIn PDF document text
    • http://muzeumostrowiec.pl/obrazy/file/dupozoseni.pdfIn PDF document text
    • http://abpaluso.com/upload/file/nejotiviveziserume.pdfIn PDF document text
    • http://miamiokclassof65.com/clients/d/db/dbefc63a503cf3d3a4f9fb61678ecc08/File/lepegolukeb.pdfIn PDF document text
    • https://winston-woodward.com/wp-content/plugins/super-forms/uploads/php/files/24944377778d5af2f58d186f7e8b3a02/84189783537.pdfIn PDF document text
    • http://dichvuwebsites.com/media/ftp/file/24147812817.pdfIn PDF document text
    • http://www.risingstars.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160fa87eab5fbd---dumumaganibuku.pdfIn PDF document text
    • http://zhouzhuank.com/v15/Upload/file/2021922044345742.pdfIn PDF document text
    • https://messianic.live/wp-content/plugins/super-forms/uploads/php/files/8bb4f6ce7c0b2cd70de399963cbc60db/kukokobabajokubepawizoveg.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_off00010106.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10106 22080 bytes
SHA-256: 9680fea2bd2170c0d030988df29bd2dbe4200f7c30e805a0c787cbe5abbd1a42
font_01_sfnt_off000138c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x138C4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000150db.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x150DB 10936 bytes
SHA-256: 0ab63d5d9d4833945f1f205062627863f6f24ce4c4642a68a425d3b4bf3003ee