Malicious PDF — malware analysis report

Static analysis result for SHA-256 27a891e264e747e7…

MALICIOUS

PDF

70.7 KB Created: 2021-09-10 15:48:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 63ae73cca2611a5d7a7134e148209f4e SHA-1: 2b8e9693bb242559190093a345809a8826cb79dc SHA-256: 27a891e264e747e732988a22a1b425a6c67ebbb1a7663d74a58bb257c759068f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many pointing to compromised WordPress upload directories, suggesting it functions as a link farm. The presence of these links, particularly those with 'utm_term' parameters, indicates an attempt to direct users to potentially harmful external sites, possibly for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://wastran.ru/uplcv?utm_term=rom+super+mario+64+para+android PDF link annotation
    • http://antik-cafe-bergen.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613a288fb28c3---4706200983.pdfIn PDF document text
    • http://neuchina.org/userfiles/file/76332676044.pdfIn PDF document text
    • https://everestart.com/images/stories/file/35230154193.pdfIn PDF document text
    • https://apatity.verlauf-ekb.ru/admin/ckfinder/userfiles/files/pekupeleweguvomitet.pdfIn PDF document text
    • http://gzhangqin.com/uploadfile/files/sipitalena.pdfIn PDF document text
    • https://led7.ru/file/37914133653.pdfIn PDF document text
    • http://sieuthibongda.net/ckfinder/userfiles/files/64475108666.pdfIn PDF document text
    • http://lnv-cnc.gr/userfiles/file/43447316232.pdfIn PDF document text
    • http://barrybusiness-crm.com/ressource/devis-photo/files/3788821973.pdfIn PDF document text
    • http://morenoroofing.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138d12652a31---72495289292.pdfIn PDF document text
    • http://studionegro.net/userfiles/files/zejofajeregifeva.pdfIn PDF document text
    • http://jockmurray.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130c2eb88a68---suxuzipifititefoduto.pdfIn PDF document text
    • https://quangcaowebsite.xemlaco.com/uploads/files/43715651703.pdfIn PDF document text
    • http://emilymillerlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/24535684316.pdfIn PDF document text
    • https://masterjobintl.com/ckfinder/userfiles/files/kewuxasebezu.pdfIn PDF document text
    • https://ymvii.com/admin/upload/files/xijibogo.pdfIn PDF document text
    • https://businesslife.com/content/files/bonapipuvebo.pdfIn PDF document text
    • http://thuexedanang247.com/uploads/image/files/92768651922.pdfIn PDF document text
    • http://uniquehotelsolutions.com/files/others/punikinogolufawajawon.pdfIn PDF document text
    • http://dmhu.eu/uploads/uplib/file/separaviterolanukari.pdfIn PDF document text
    • https://arendic.cl/files/96639249104.pdfIn PDF document text
    • https://mkting.com.co/wp-content/plugins/super-forms/uploads/php/files/b87762d82e75b15d7bc7f1452defd575/62482109585.pdfIn PDF document text
    • http://saraiaser.nl/userfiles/file/55528031590.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_off0000b21b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB21B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ca32.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA32 10800 bytes
SHA-256: e672a562ba34b792c05357e5ebd754ad16fdfa9f603e55d28ad3b13061963b33
font_02_sfnt_off0000e314.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE314 16452 bytes
SHA-256: f95ce7f5e1b81e761cb556c6cebf82686ff755ea11dae6b424e163c94dbe573b