Malicious PDF — malware analysis report

Static analysis result for SHA-256 63da9accded9c3eb…

MALICIOUS

PDF

78.0 KB Created: 2021-06-17 10:25:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-04
MD5: 039e45ba4fb00223f675d9080bdfb234 SHA-1: 8e7ea761ae6b00931315b7c7d6f03a4d08673452 SHA-256: 63da9accded9c3ebec89979b4a70a6b1b7b7a94a98532eef730af3ed9bd3a628
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 0.9998

Heuristics 7

  • 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.
  • 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://chcial.ru/uplcv?utm_term=nda+exam+questions+and+answers PDF link annotation
    • https://118highschool.am/wp-content/plugins/super-forms/uploads/php/files/24a4e19ee190e2a5fd74b77ddd24520e/85810950841.pdfIn PDF document text
    • http://x04ydivan.ru/userfiles/file/lenewapotemuwonen.pdfIn PDF document text
    • http://villaturri.it/wp-content/plugins/formcraft/file-upload/server/content/files/1608d1959a4a22---zarebanavapuvija.pdfIn PDF document text
    • http://derma-dts.de/files/file/nozokesu.pdfIn PDF document text
    • https://bdaudit.ro/userfiles/file/dipadejisanukada.pdfIn PDF document text
    • https://www.pennlighting.com/wp-content/plugins/super-forms/uploads/php/files/96d1a190f01b992cd4ef77398bbc6538/64152536399.pdfIn PDF document text
    • https://alshaabcoop.com/userfiles/file/26857194578.pdfIn PDF document text
    • http://www.onekaddy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8b1a282aec---13566153602.pdfIn PDF document text
    • http://k-yoga.org/file_upload/spaw_upload/file/20210520032320.pdfIn PDF document text
    • https://braviengenharia.com.br/wp-content/plugins/super-forms/uploads/php/files/4990oqd3i86lmqdk0ctrn5dqdr/bupusaf.pdfIn PDF document text
    • https://protechlighting.com/wp-content/plugins/super-forms/uploads/php/files/63afd3511afcff025bfb772367d65d96/20598323605.pdfIn PDF document text
    • http://cgt-fo-csc.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160843f1e0032c---63499651965.pdfIn PDF document text
    • https://emergent-partners.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c100433eb9e---30415837304.pdfIn PDF document text
    • https://travelselection.us/wp-content/plugins/formcraft/file-upload/server/content/files/160a559310dbb3---zonagakozapitomaro.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_off0000f44c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF44C 5196 bytes
SHA-256: 87ec851b61e23e35f70d778260f97f15859e4f1b0c81314e4eee77430690a067
font_01_sfnt_off000105f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105F6 10884 bytes
SHA-256: e07cb4d873aa42363699e99aded82746809b72fa004c4f5905a8c5375333525b