Malicious PDF — malware analysis report

Static analysis result for SHA-256 9654d9b91311585a…

MALICIOUS

PDF

79.1 KB Created: 2021-09-06 18:42:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 36a50d6fea68403e1753fe5ebf9c6a31 SHA-1: f6f6cb6d2d68c2a97a0323cf0b15e28a11c3d016 SHA-256: 9654d9b91311585aa3a3725d7816978c0a2e247407a8539fa708daf6e5c30c78
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many pointing to compromised websites or disposable hosting, indicating a link farm designed to lead users to malicious content. The ML classifier and ClamAV detection strongly suggest this PDF is malicious, likely for phishing or malware distribution. No scripts were extracted, and the document body was unreadable, but the heuristic firings clearly indicate a malicious link distribution pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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://krisoc.ru/uplcv?utm_term=speech+marks+worksheets+for+grade+2 PDF link annotation
    • https://sv-fin.ru/wp-content/plugins/super-forms/uploads/php/files/315e91b8fd4e145f081cee395ec321f0/42770446781.pdfIn PDF document text
    • http://americandeliorder.com/uploads/files/bivavapilar.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160c49741c96c5---70614083098.pdfIn PDF document text
    • https://mimpishiosatu.com/contents//files/55235218365.pdfIn PDF document text
    • https://www.lipfish.no/wp-content/plugins/formcraft/file-upload/server/content/files/16089a844b6417---fevejusorutiravu.pdfIn PDF document text
    • https://yingzhaoliuart.com/upload/file/85132407390.pdfIn PDF document text
    • http://adamlegal.com/userfiles/file/vamisavubuluv.pdfIn PDF document text
    • https://frasertechno.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080de81d03aa---wejotegodeziweje.pdfIn PDF document text
    • https://aradovan.com/userfiles/file/9152681908.pdfIn PDF document text
    • http://njf724.com/basefile/janatalnajafcom/files/jivijiloriluledarogal.pdfIn PDF document text
    • http://thinhhoanggia.vn/Images_upload/files/vezategulas.pdfIn PDF document text
    • https://elitteaccesorios.com/wp-content/plugins/super-forms/uploads/php/files/n12h0q08bo5ir75e9fh29gi18s/jigivaf.pdfIn PDF document text
    • https://carstenrath.com/wp-content/plugins/super-forms/uploads/php/files/1kbpj9p2oc1d5epof8rv539aop/zirido.pdfIn PDF document text
    • https://www.conkite.com/wp-content/plugins/super-forms/uploads/php/files/cbd1bde08847f01c9c1f6d821332509d/lirusimuvigalawojapi.pdfIn PDF document text
    • http://neilreardon.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/11112776365.pdfIn PDF document text
    • http://kag.fr/userfiles/file/73363251448.pdfIn PDF document text
    • http://kowel.com/ckfinder/userfiles/files/1630267267.pdfIn PDF document text
    • http://dui-antidote.net/images/userfiles/file/genivawotibinifosizokoxap.pdfIn PDF document text
    • http://www.scsi.coop/wp-content/plugins/super-forms/uploads/php/files/bb072bd35cc36445e9404c0b91f6c501/96966384130.pdfIn PDF document text
    • https://eternalbliss.net/file/65576140660.pdfIn PDF document text
    • http://zaintik.org/files/galeria/files/morenefusafo.pdfIn PDF document text
    • http://centrlita.ru/archive/image/file/38188797153.pdfIn PDF document text
    • http://www.firengo.com/userfiles/files/sisuwotedafalekijik.pdfIn PDF document text
    • http://thuephotocopytaihanoi.com/upload/files/99340442119.pdfIn PDF document text
    • https://whitelightdesign.com/wp-content/plugins/super-forms/uploads/php/files/c1170799c44fe2030e45138035a3ddd1/86767344538.pdfIn PDF document text
    • https://cdmsig2.com/ckfinder/userfiles/files/jigomomuxa.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_off0000cbd7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCBD7 11196 bytes
SHA-256: 23bb987d04c95344aff5b7c206abe406605584e13014ad523c7fa3e247a2ba22
font_01_sfnt_off0000e602.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE602 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fe14.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE14 18636 bytes
SHA-256: e80979a399a11956608bdd7247fc81977ffc89b5504c8f8375f0f10cd2a1c3bb