Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef82675d68908912…

MALICIOUS

PDF

86.1 KB Created: 2021-09-02 04:27:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5d9c4b6a46eacbc08bf8dc22d84b8540 SHA-1: f38bcc5f484ddd328d6162078df93bc61888c3f1 SHA-256: ef82675d68908912c4ef208ea9d3a753b5ec4dbf7f2cda0b051bb403a1c13d8d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. It contains numerous embedded URLs pointing to compromised CMS uploads and disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The file's structure and embedded content indicate it is likely used as a lure, potentially for phishing or to download further malicious payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://synerhu.ru/uplcv?utm_term=digital+electronics+lecture+notes+pdf
    • http://cafesezony.ru/fck_editor_files/files/7287113621.pdf
    • https://visualarchive.bg/files/vomowa.pdf
    • http://www.rify.us/cms-uploads/files/9842284114.pdf
    • http://oreade-breche.fr/userfiles/file/91372097099.pdf
    • http://sztarmedia.hu/_user/file/67425523548.pdf
    • https://esteticarcare.com/wp-content/plugins/super-forms/uploads/php/files/c7dd972d27c801d35d41c99b6a588293/61013191415.pdf
    • https://fietenhaardenenkachels.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1608d1aee51664---47697479797.pdf
    • https://provisionsinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1611dd89f01fcb---33930445988.pdf
    • https://bloc-immo.com/images/24512100215.pdf
    • https://smarttactic.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16092ba7d22035---63728759643.pdf
    • http://www.dogwoodagility.nl/ckfinder/userfiles/files/67601761157.pdf
    • https://fiberglasssupplydepot.com/userfiles/file/nanagabiropukomijuzosemi.pdf
    • https://thefencedocumentary.com/adminfiles/file/gimuxo.pdf
    • http://waterreducer.cn/d/files/983438766.pdf
    • http://caopump.com/admin/userfiles/file/pumukujurelotukibakuvefa.pdf
    • http://aviatechinform.ru/sadm_files/57723535877.pdf
    • https://nceptionsolutions.com/wp-content/plugins/super-forms/uploads/php/files/6c5766f96449249a539ae1093b2d9690/90095063564.pdf
    • https://www.criteriainvest.com.br/wp-content/plugins/super-forms/uploads/php/files/0gbmevr8rieom4mni86gqlq8nl/93330504924.pdf
    • https://beaszemin.com/files/30598260310.pdf
    • https://www.mclarenpress.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b5af418d7d---rebizalasilavenu.pdf
    • https://asiaviews.org/wp-content/plugins/super-forms/uploads/php/files/otm48lqo1klk54k8hqt2li9nl5/pikaguruvakajuloduxafi.pdf
    • https://hanmarklight.com/UploadFile/files/kososopibulenubamepu.pdf
    • https://heykidsletscook.info/wp-content/plugins/super-forms/uploads/php/files/efeac3004846b3427639b967ac27cd4f/80562141533.pdf
    • http://www.moteco.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1607b04804e480---21064574859.pdf
    • http://lagrupacio.cat/file/40326808640.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_off0000e994.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE994 16792 bytes
font_01_sfnt_off000101ab.bin
f6d74df948897a57e289da232622fa8433bb8fd88815981ebd5e3d90c10f2138
pdf-font-stream PDF embedded font (sfnt) at offset 0x101AB 10896 bytes
font_02_sfnt_off00011ac5.bin
09a8ebce993585d9ddf313f886d642ede438bf3c3e6247773f95c2babf740aae
pdf-font-stream PDF embedded font (sfnt) at offset 0x11AC5 18316 bytes