Malicious PDF — malware analysis report

Static analysis result for SHA-256 586b8fdd42b7a61e…

MALICIOUS

PDF

81.9 KB Created: 2021-05-26 07:47:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-04
MD5: c93c0d2fdeeb537445a7eff17d286ce8 SHA-1: bcb5535d02884c9a280ee236063122b50aa3a3be SHA-256: 586b8fdd42b7a61ea0177357c849441f6a2fa0891e76f5a3322c883ee8ed2421
164 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and presents a deceptive download button. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://huntic.ru/uplcv?utm_term=computer+systems+a+programmer%2527s+perspective+3rd+edition+online+pdf PDF link annotation
    • https://atlastoursntravels.com/userfiles/file/laluxugumepu.pdfIn PDF document text
    • https://nscs.org/wp-content/plugins/super-forms/uploads/php/files/de7c8e6bb0921896cd1efbb119a28d94/9830378718.pdfIn PDF document text
    • https://coluer.ir/documents/file/80467364578.pdfIn PDF document text
    • http://endustriyelkiralama.com/wp-content/plugins/super-forms/uploads/php/files/e18p7h6q8il25as6662uqnd9pm/getisipevovotavela.pdfIn PDF document text
    • http://mko-yug.ru/wp-content/plugins/super-forms/uploads/php/files/d0d365654d9254258f01db154dc35c65/lodepugelavelobejamegopuk.pdfIn PDF document text
    • http://altaprecision.com/userfiles/file/68383897315.pdfIn PDF document text
    • https://mattweidnerlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076172718538---fikukanela.pdfIn PDF document text
    • http://botanicgardenscafe.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607b77134a80b---29408365417.pdfIn PDF document text
    • http://www.hypnotiseur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607818ae830cf---badenukorixuponosu.pdfIn PDF document text
    • https://yziact.fr/wp-content/plugins/super-forms/uploads/php/files/lhgjlh291213tj8bfmbppup457/kanomobatewazoj.pdfIn PDF document text
    • https://vandolderskb.com/images/usr/34165874976.pdfIn PDF document text
    • https://airbays.com/userfiles/file/zaputumojakefizuwapole.pdfIn PDF document text
    • https://anpheatingandac.com/nbloom/fckuploads/file/63237676832.pdfIn PDF document text
    • https://genesislighting.net/wp-content/plugins/super-forms/uploads/php/files/1806d58eaa1cf39829d976ae64d7b1f3/42471631475.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000101a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101A4 5740 bytes
SHA-256: d7e9f72abbe88a296da46073aaebf5e95a892b97a8b624ecde1474a8c52414d0
font_01_sfnt_off0001152e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1152E 10808 bytes
SHA-256: 85934790227da8ff15766d84153691b90d84e29215dd519d464e8674af75e95f