Malicious PDF — malware analysis report

Static analysis result for SHA-256 f80fd2b3099cae49…

MALICIOUS

PDF

84.5 KB Created: 2021-09-22 09:34:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 5889e941ac1d7cf548d25dfb302aab41 SHA-1: 6d193c4faa880b2a4a1340975884868102d4018e SHA-256: f80fd2b3099cae49e880fc5396ed872f99f79b825927d5a3c3fe837f4286d523
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

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, directing users to multiple external websites, some hosted on compromised CMS platforms. The presence of numerous URLs, many using 'utm_term' parameters, suggests an attempt to disguise malicious links and potentially track user engagement for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://irlanc.ru/uplcv?utm_term=justice+league+snyder+cut+trailer+download PDF link annotation
    • https://claphamjunction.com.au/wp-content/plugins/super-forms/uploads/php/files/dc4b3781153303cffd9d321aa992913b/vekufagomo.pdfIn PDF document text
    • http://oilspecchem.com/files/nasazeginemowukuzagesinok.pdfIn PDF document text
    • http://khonggianmang.com/upload/files/28321895681.pdfIn PDF document text
    • http://dogomanhnghia.com/uploads/files/62369170610.pdfIn PDF document text
    • https://semagro-msw.ru/pics/images/file/45665407158.pdfIn PDF document text
    • http://wang023spa.com/userfiles/202109file/2021090710251270554.pdfIn PDF document text
    • http://nelly-design.ru/upload/files/zifopedamodatawasozap.pdfIn PDF document text
    • http://beerskiboot.de/img/upload/file/68560364803.pdfIn PDF document text
    • http://angel-conference.org/upload_fck/file/2021-9-17/20210917144525358629.pdfIn PDF document text
    • http://clickvay.com/upload/files/nuvof.pdfIn PDF document text
    • https://www.fangjin.org/ckfinder/userfiles/files/7012571851.pdfIn PDF document text
    • http://baharemadinah.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c1d7192dd2---boparufujid.pdfIn PDF document text
    • https://bursac.net/userfiles/file/xekavamogajuxa.pdfIn PDF document text
    • http://bridgesonthepark.com/wp-content/plugins/formcraft/file-upload/server/content/files/161332831a29b8---80006412402.pdfIn PDF document text
    • https://guineaservicesproviders.com/gsp/files/87565966089.pdfIn PDF document text
    • http://malagi.pl/user-files/fck/file/roredekolov.pdfIn PDF document text
    • http://tomaszskiba.com/userfiles/file/30313703847.pdfIn PDF document text
    • https://1tlstar.com/storage/uploads/files/76922544469.pdfIn PDF document text
    • https://wrd13.com/force/file/39346353655.pdfIn PDF document text
    • https://sodigital.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613aa81aeb1a7---85605433677.pdfIn PDF document text
    • https://hardlineconstruct.ro/app/webroot/files/userfiles/files/fapusaniwivunizinarimup.pdfIn PDF document text
    • https://stephankeppel.com/userfiles/file/zesukozexigafis.pdfIn PDF document text
    • http://mp-journal.com/media/file/saviwor.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_off0000daf1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAF1 21156 bytes
SHA-256: e6bbdcb4ed915d07147810163b819e7a107c9332e3d1fbe57f933a313a0dfb22
font_01_sfnt_off000112dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x112DD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012af4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12AF4 10836 bytes
SHA-256: f983bf36fed99bd6184b59ff5be6a86eeb6b45e682680aea2e56f1018c43ec6e