Malicious PDF — malware analysis report

Static analysis result for SHA-256 ad8e652d6abfb73b…

MALICIOUS

PDF

90.4 KB Created: 2021-09-13 16:51:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: c5b5615af8a3633df5d280fd7e94018d SHA-1: 5deb5f594c5fc907f8766f9843e1ec3e551d0445 SHA-256: ad8e652d6abfb73b439f62665320a8c8cccb8b07c65ceca6800bb195bfb72d7f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ML classifiers and ClamAV, specifically as a PDF phishing trojan. It contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, suggesting a link farm or phishing lure. The presence of external URI heuristics and link farm indicators strongly supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://ketchas.ru/uplcv?utm_term=how+to+increase+call+log+history+in+android PDF link annotation
    • http://eapver.com/upload/ckimg/files/202109081612134306.pdfIn PDF document text
    • http://mylodge-naoshima.com/tagesogulanu.pdfIn PDF document text
    • http://www.appsolutely.sg/wp-content/plugins/formcraft/file-upload/server/content/files/1613dfc8d58162---47992126579.pdfIn PDF document text
    • http://vishwkarmaenterprises.com/webroot/img/userfiles/files/19261679642.pdfIn PDF document text
    • http://thebankcardservices.com/uploads/files/59076734117.pdfIn PDF document text
    • http://www.kinoimaging.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16131feacb79d6---dulekizisanalazesu.pdfIn PDF document text
    • http://sushimura1.com/uploads/files/56922228171.pdfIn PDF document text
    • https://cherrychile.cl/cherry/uploads/contenido/files/35316469838.pdfIn PDF document text
    • http://www.520amis.com/upload/files/dawegiserorijiw.pdfIn PDF document text
    • http://thingsantiquesla.com/userfiles/files/visasuwek.pdfIn PDF document text
    • http://scbczy.cn/up_files/file/20210906_103344.pdfIn PDF document text
    • https://highlander-inn.com/assets/userfiles/files/75055860279.pdfIn PDF document text
    • https://nuregio.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613a1df729d28---54464293190.pdfIn PDF document text
    • http://tcsklife.com/filespath/files/20210907161529.pdfIn PDF document text
    • https://bruceautoservice.com/files/file/rikoda.pdfIn PDF document text
    • http://tamtamphat.com/upload/files/zugakidimewakutuxage.pdfIn PDF document text
    • https://jaunimodienos.lt/wp-content/plugins/super-forms/uploads/php/files/f8mbhi1po9rhhr07j5ajktn4h0/vopodidogowon.pdfIn PDF document text
    • http://aiswaryamatrimonials.com/fck_uploads/file/faxakeze.pdfIn PDF document text
    • https://doublehaircenter.com/upload/ckfinder/files/42150523724.pdfIn PDF document text
    • http://architettobotteonpierpaolostudioabacus.it/userfiles/files/buxetudefujotibofirara.pdfIn PDF document text
    • http://sns-russia.ru/userfiles/file/35566913277.pdfIn PDF document text
    • http://asu78.ru/userfiles/file/89677288393.pdfIn PDF document text
    • https://ladymamashop.com/uploads/files/202109051612339431.pdfIn PDF document text
    • http://electriccityusa.com/images/fck_uploads/file/ranisulevodupemowuvumowol.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_off0000fdc7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDC7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000115d9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115D9 17380 bytes
SHA-256: f3c4a74d041fb9366c036eff97a85edef8d29638a85fba5eb45264fe974ac3ef
font_02_sfnt_off000142a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x142A7 10840 bytes
SHA-256: 4e8592799fc0a8c114d38cd072e6e4dc407effe7fc325fe7150289ad15817856