Malicious PDF — malware analysis report

Static analysis result for SHA-256 fd78151e990fb4a9…

MALICIOUS

PDF

86.7 KB Created: 2021-07-02 13:44:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 17f2c0f01c4dc0889e1399d00ec2c348 SHA-1: 4063d7ef4170416c66f76f7bc3dda9b6b6938c49 SHA-256: fd78151e990fb4a9e055a5a5148b0d1d1a2f530fb4042e0888ccd055c8eda3bb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to other PDF files hosted on compromised WordPress sites. The presence of external URIs and link farms suggests an attempt to distribute malicious content or conduct phishing attacks. No scripts were extracted, but the overall structure points to a multi-stage attack leveraging compromised infrastructure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://pistant.ru/uplcv?utm_term=graphing+lines+sketch+the+graph+of+each+line
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/16084faf86e8ba---18066904710.pdf
    • http://bezpiecznamlodosc.org/files/file/16384828353.pdf
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/16086488299440---vasaletukiwamagafilo.pdf
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/160983922db56c---sopopilu.pdf
    • http://elitakhealing.com/ckfinder/userfiles/files/dijadimuvudejuradoxunepip.pdf
    • http://sendedianqi.com/upload_fck/file/2021-6-12/20210612085241317608.pdf
    • https://makemycake.gr/wp-content/plugins/super-forms/uploads/php/files/a4mmh29olj8pbrongc5rktfmnr/32009952819.pdf
    • https://swotin.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c23a917cfd---51655104100.pdf
    • https://kaxtongroup.com/home5/maxconne/public_html/kaxtongroup/assets/images/newspostimages/files/xenemen.pdf
    • http://skincarebylaura.com/clients/862251/File/66589386510.pdf
    • http://eszixv.hu/ckfinder/userfiles/files/kitekune.pdf
    • https://texigo.tw/upfile/files/2021/06/23/bazuri.pdf
    • https://wholisticvibrations.com/wp-content/plugins/super-forms/uploads/php/files/67271447aeb290f26a59d3c3bcfa30f6/12781687663.pdf
    • https://agentcctv.com/userfiles/file/sutedogugogatimuniv.pdf
    • http://mijneigenlift.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1609af59a7a4b1---getimujitatodenukev.pdf
    • http://africanhairbraidingsalon.com/userfiles/file/gabajunujekewopibavin.pdf
    • http://elmiraclassiccountry.com/wp-content/plugins/super-forms/uploads/php/files/k8q0s584nrlpkf5meop1ujcud5/ranevipejujogebib.pdf
    • http://cageart.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160c590c9e4e25---soxezipex.pdf
    • https://weblative.com/wp-content/plugins/super-forms/uploads/php/files/k39q465r9juvpb2c3gkpue5jft/20567686054.pdf
    • http://fresh-j.info/images/uploadedimages/file/61804931197.pdf
    • http://www.majoriscambio.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b5054340629---bepodotatiraji.pdf
    • http://www.combatsim.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160b473a2653f2---61509228981.pdf
    • https://siphouse96.com/wp-content/plugins/super-forms/uploads/php/files/2fc6b8388377bb976d3f31c145616729/88586680133.pdf
    • https://ngoctraithaibinhduong.com/uploads/news_file/4185129697.pdf
    • http://studiotecnicodavico.eu/userfiles/files/mirakaxidigakimewimuku.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000efbc.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEFBC 16792 bytes
font_01_sfnt_off000107d3.bin
2583e31c6aeed319e122e02030456c06a612b99abd8851b0061ecf1f7fff805a
pdf-font-stream PDF embedded font (sfnt) at offset 0x107D3 10892 bytes
font_02_sfnt_off000120fd.bin
97b9de107e8169a8b75860087809e4cab9e0f43b08e4bc09539a7a402bd66bf5
pdf-font-stream PDF embedded font (sfnt) at offset 0x120FD 16960 bytes