Malicious PDF — malware analysis report

Static analysis result for SHA-256 a85868c4f1746fb5…

MALICIOUS

PDF

86.7 KB Created: 2021-08-03 12:55:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 063c9657a60e0a29e8b39ac6c46c26d1 SHA-1: b791a83c4165aa3e6a2e24df75ad2cb10c00750a SHA-256: a85868c4f1746fb507692877b176acbc4d2598ccd1c178aaf5197ba92863217a
164 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous URLs pointing to potentially compromised or disposable hosting. The document body is heavily obfuscated, preventing a clear understanding of its specific lure, but the overall structure and detection results strongly suggest a malicious intent to redirect users to harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

Heuristics 7

  • 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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://fixafilm.se/userfiles/file/fojazazuwixapefejepakepaw.pdf In PDF document text
    • http://sushiloverca.com/uploads/files/xoromajurejakuwuva.pdfIn PDF document text
    • http://www.bestlifepolicy.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160b6023c0bdfe---guliwik.pdfIn PDF document text
    • http://xn--b1ahhafccpgkb2bxo.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/1487c1fced97e1dd17fe966997692af6/96164557316.pdfIn PDF document text
    • http://bolshunoff.ru/images/wysiwyg/file/42337305989.pdfIn PDF document text
    • http://vivaibonomo.it/userfiles/files/97009651558.pdfIn PDF document text
    • http://ricoconsultingattorney.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/matonifelanoxawiporedozi.pdfIn PDF document text
    • https://gaseg.com/wp-content/plugins/super-forms/uploads/php/files/vhjtoph184mf56lrhldtcsh7hv/80175887435.pdfIn PDF document text
    • https://robinio.de/wp-content/plugins/super-forms/uploads/php/files/dau2eadckjgef437uvr47sb91f/nekabapumexaneka.pdfIn PDF document text
    • https://footballsod.com/images/ck-uploads/files/jirul.pdfIn PDF document text
    • http://www.johnknox.ch/wp-content/plugins/formcraft/file-upload/server/content/files/16071ecb0956c1---34650119778.pdfIn PDF document text
    • http://podhoru.cz/userfiles/file/70422686954.pdfIn PDF document text
    • http://sciencevier.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a888298b5c---nupubuxofoda.pdfIn PDF document text
    • https://psychologgia.pl/Upload/file/torinedewedowiju.pdfIn PDF document text
    • http://sacmacbook.net/userfiles/file/sibizuki.pdfIn PDF document text
    • http://www.191seo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c94a9fb4164---3751467851.pdfIn PDF document text
    • http://www.trafikyaren.com/wp-content/plugins/super-forms/uploads/php/files/n985nhp6g8p36610k7mf665bm4/66495890679.pdfIn PDF document text
    • http://teknis.it/userfiles/files/zikefapani.pdfIn PDF document text
    • https://www.ideaklinikankara.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608079f383ce0---5013480825.pdfIn PDF document text
    • http://centronegozi.com/public/76925794905.pdfIn PDF document text
    • https://villatoscana-pi.it/userfiles/file/vazawasafuwuwugumoga.pdfIn PDF document text
    • https://hkbca.org/UploadFiles/file/20210712220204181.pdfIn PDF document text
    • https://www.fifatravels.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f6f2fc76ac---tedab.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=contents+of+a+dead+man%27s+pocket+analysisPDF 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_off0000ef72.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF72 16684 bytes
SHA-256: ef3c2dbf43a37ac5c48e783e5a4f6e5c784bd50bc8a17273c4ed84c1f2a1725b
font_01_sfnt_off00011a75.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A75 10952 bytes
SHA-256: 459c8f5381718d1ff7742d61918fa5aa95e2b0dfadff4a46a9a2af5c1b495f38
font_02_sfnt_off000133fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x133FA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1