Malicious PDF — malware analysis report

Static analysis result for SHA-256 a92da9ff092ee663…

MALICIOUS

PDF

82.5 KB Created: 2021-10-11 22:34:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 52a25a3f247315a57939b817e0b81fd2 SHA-1: 085d3bd51007e8152e7ca1016f95e723018db013 SHA-256: a92da9ff092ee663b5db94b76252362c49ab7ace55f53c29fff5b2cc6127a07a
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to compromised WordPress sites, suggesting a link farm or SEO poisoning tactic. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution via these links. No scripts were extracted, and the document body was unreadable, so the primary attack vector appears to be the embedded URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

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://queure.ru/uplcv?utm_term=tailoring+wow+classic+leveling+guide PDF link annotation
    • http://adamlegal.com/userfiles/file/lutufasorifetuvamefowur.pdfIn PDF document text
    • http://goldmustang.com/files/files/67778738640.pdfIn PDF document text
    • http://chagatea.ru/wp-content/plugins/super-forms/uploads/php/files/0fa3afd55f21f1f7e1003ffae03671bd/fogexawumebemesopurepir.pdfIn PDF document text
    • http://vpsystem.com/files/fck/45959931930.pdfIn PDF document text
    • https://xn--80apefbdm9ah5g.xn--p1ai/userfiles/tusabex.pdfIn PDF document text
    • http://www.stallionreadymix.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1614fca1460ed0---kiratepexetoputudaji.pdfIn PDF document text
    • https://www.infratechgroep.nl/wp-content/plugins/super-forms/uploads/php/files/f71fd148c5a4d0b0d9db372fbd75a02d/kewikalozojebazuwojos.pdfIn PDF document text
    • https://bunian-co.com/other_files/File/84367599301.pdfIn PDF document text
    • https://matricula.hssanesteban.cl/files/39555074060.pdfIn PDF document text
    • http://s-pack.kr/userfiles/file/20210913022411.pdfIn PDF document text
    • http://obrazyramix.pl/userfiles/file/89999055566.pdfIn PDF document text
    • http://renknh.com/ckupload/files/wuwemuzifovojaju.pdfIn PDF document text
    • https://pustelnik-budownictwo.pl/ckfinder/userfiles/files/mafoxofitufu.pdfIn PDF document text
    • https://foundlight.ca/home/foun6192/public_html/files/custom_files/file/78887833286.pdfIn PDF document text
    • https://questyme.com/userfiles/file/farofozevomugowuzonurutet.pdfIn PDF document text
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/srv9im9oaohbvutbohfk203qj6/kirigevumuwesow.pdfIn PDF document text
    • http://gzafjc.com/uploadfile/files/pitunomuzudixijaziwemuvut.pdfIn PDF document text
    • http://xn--o39a91gvwm83kbsn.com/FileData/ckfinder/files/20211001_1ED635930E01409C.pdfIn PDF document text
    • http://mannaz.pl/userfiles1/file/94323032743.pdfIn PDF document text
    • http://streathamtaxi.com/survey/userfiles/files/damowopupokakepunekovo.pdfIn PDF document text
    • http://everintelconsulting.com/upload/file/202109211828351455.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_off0000dc22.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC22 18628 bytes
SHA-256: 77c59bfddc7e84f9da836e4d552a0cd449be719ea4e4f498f46035df6eee9f1a
font_01_sfnt_off00010c4a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C4A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012461.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12461 10660 bytes
SHA-256: 85af69f5d15af99316d0868c0c3c398cc57121e459dad35de2b31edd29d8f101