Malicious PDF — malware analysis report

Static analysis result for SHA-256 09c87caf112ce369…

MALICIOUS

PDF

69.4 KB Created: 2021-09-13 20:38:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 7990d5fe20a4df4d0ed85c26f06c6c29 SHA-1: cf664f27695a2709769019f3315555792994cce6 SHA-256: 09c87caf112ce369080bfd5a0525e8cda8ac006adf04ae08e2c57eb5145c314d
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, many hosted on disposable domains or compromised WordPress sites, indicative of a link farm used for phishing or malware distribution. The ClamAV detection and ML classifier strongly suggest malicious intent. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' further supports the nature of the document as a collection of links to potentially malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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=how+to+look+at+downloads+on+android PDF link annotation
    • http://heaig.org/editor/ckfinder/userfiles/files/2656704183.pdfIn PDF document text
    • http://hybsch.it/upload/file/43841191091.pdfIn PDF document text
    • http://dailygameresult.com/editor/UserFiles2/files/47775666013.pdfIn PDF document text
    • http://grandfiltr.com/files/file/gedofamemepujazufifiwut.pdfIn PDF document text
    • http://tomgiongvip.com/uploads/files/file/begusaj.pdfIn PDF document text
    • http://www.maoles.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a1fc26b986---11373532575.pdfIn PDF document text
    • https://12tiga.com/contents/files/jotoseku.pdfIn PDF document text
    • http://skupka23.ru/upload/m/patutukidetej.pdfIn PDF document text
    • http://ovecollection.com/royal/admin/images/products/file/51183456548.pdfIn PDF document text
    • http://restavratorstvo.com/ckfinder/userfiles/files/22265758310.pdfIn PDF document text
    • http://cyc.cz/pictures/clanky/files/xegabip.pdfIn PDF document text
    • https://www.pelicanfinancialnetwork.com/ckfinder/userfiles/files/50141898313.pdfIn PDF document text
    • http://gordostcrista.ru/userfiles/file/mavuxiwutakari.pdfIn PDF document text
    • http://www.barankayalar.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16137e5870982b---1898491507.pdfIn PDF document text
    • https://www.capitalroofingct.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f6a0f1da49---zewiw.pdfIn PDF document text
    • https://unitytradecapital.com/ckfinder/userfiles/files/20385942208.pdfIn PDF document text
    • http://www.farparts.cl/wp-content/plugins/formcraft/file-upload/server/content/files/16130ad6cf401f---1475437105.pdfIn PDF document text
    • http://cheliabinsk.realxenon.ru/uploads/files/92604376190.pdfIn PDF document text
    • http://www.yemany.com/yemfiles/files/12341960682.pdfIn PDF document text
    • http://z-i-f.ru/userfiles/file/64751097552.pdfIn PDF document text
    • http://counterreaction.net/wp-content/plugins/formcraft/file-upload/server/content/files/16139a9f5e87f4---82891617989.pdfIn PDF document text
    • http://wsm.hk/images/uploadfiles/file/zuvojometixizi.pdfIn PDF document text
    • http://ayhancevik.com/images_upload/files/miwobavudepif.pdfIn PDF document text
    • http://donauwell.at/userfiles/file/wutupibovigumimibetasa.pdfIn PDF document text
    • http://ieltsadd.ir/cache/fck_files/file/famokajorojugaxegubaj.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_off0000b442.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB442 14580 bytes
SHA-256: 4bbcf05763ddf1214f9f6e2777df9624a1119a2a14d6f6f290e70cfe6b2d377a
font_01_sfnt_off0000d813.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD813 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f02a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF02A 10280 bytes
SHA-256: 6b426b35691bbee76a5d10ad75b10205740c44b4211351d8009520051397155e