Malicious PDF — malware analysis report

Static analysis result for SHA-256 c1fb0b244997d86f…

MALICIOUS

PDF

88.3 KB Created: 2021-09-14 10:03:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: dc64cf7c5cf2d27c4e50cafd6546ab69 SHA-1: ab6da5c61ac0e2a2e39ff180851bedfe23f4b04a SHA-256: c1fb0b244997d86feef45a1a584c38025cc0624f1fa093354d1b090de6c70b06
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many of which point to compromised or disposable domains, suggesting a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly indicate malicious intent. The document body is unreadable, but the heuristics and URL analysis are sufficient to infer a phishing or malware distribution 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 http://xn----8sbaqfskngn1qi.xn--p1ai/userfiles/file/wifawoxetora.pdf In PDF document text
    • http://emachn.com/data/attachment/file/62621717185.pdfIn PDF document text
    • https://candbco.com/ckfinder/userfiles/files/98415880661.pdfIn PDF document text
    • http://divapharma.com/uploaded/file/98347944704.pdfIn PDF document text
    • https://helices-evra.com/userfiles/file/fokasijarisi.pdfIn PDF document text
    • https://livnica-metalurg.com/images/pages/file/22347550529.pdfIn PDF document text
    • http://nnk.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1612ed135e46a4---31829332920.pdfIn PDF document text
    • http://sdds.be/userfiles/file/90223062873.pdfIn PDF document text
    • http://mrhobbscoffee.com/images/uploads/file/vuzepaperowete.pdfIn PDF document text
    • http://anadolumatbaa42.com/genelresimler/file/gotuzusovodunixapifomalu.pdfIn PDF document text
    • http://brava-ekb.ru/userfiles/file/gogelexun.pdfIn PDF document text
    • http://m-camper.ru/ckfinder/userfiles/files/savuvadoma.pdfIn PDF document text
    • https://www.simcoerecovery.net/wp-content/plugins/super-forms/uploads/php/files/jlt4qvp4oc04sattp4v4sq8mri/43193908482.pdfIn PDF document text
    • https://ktmcollege.org/public_html/userfiles/file/vusopavozuberoj.pdfIn PDF document text
    • http://rayer.cn/d/files/navekugujefuwizuwegoz.pdfIn PDF document text
    • http://jualumnitoronto.com/editor/uploadfiles/nubizedimolusagil.pdfIn PDF document text
    • http://ackerviewguesthouse.com/userfiles/file/vinoxinogirokefavofetaj.pdfIn PDF document text
    • https://www.marthatrotts.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613b50b7eab18---logaxajabepigirixirer.pdfIn PDF document text
    • https://herfection.herfection.tw/upload/ckfinder_temp/files/20210904015029.pdfIn PDF document text
    • http://terfigyelokamera.info/files/file/feravuxup.pdfIn PDF document text
    • http://jfac.kr/ckfinder/userfiles/files/dujegunotolomesuxa.pdfIn PDF document text
    • https://xlux.vn/wp-content/plugins/super-forms/uploads/php/files/431o53ssod3imoqa3vsjp86u4m/34865240435.pdfIn PDF document text
    • https://12shio3.com/contents/files/dajudunutigij.pdfIn PDF document text
    • http://finemetal-cn.com/upload/files/lajomupifexamivalug.pdfIn PDF document text
    • https://mimpishio2.com/contents/files/89819811752.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=how+to+find+hidden+apps+on+androidPDF link annotation
    • 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_off0000f4bd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4BD 10628 bytes
SHA-256: 53ac630a8f0860e22a08c53b789833db8c2cc76da8cdc1ea58828a9c112537da
font_01_sfnt_off00010cf7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CF7 17892 bytes
SHA-256: ef56d2ac5341805eb220e827d8d1546ebff198202b3157b4f3477e5523bc4e89
font_02_sfnt_off00013b53.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13B53 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1