Malicious PDF — malware analysis report

Static analysis result for SHA-256 291f1d5825d31115…

MALICIOUS

PDF

70.7 KB Created: 2021-05-31 03:50:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-01
MD5: 4aad4658acf0301ba2c31df38b4301b2 SHA-1: 53714c7d17b0f8be4def3061c75d590c154fb03c SHA-256: 291f1d5825d31115a2343544d0eac944785ea8b807a0e1cde20360e764ccf6e7
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://irlanc.ru/uplcv?utm_term=makey+makey+games+bongos PDF link annotation
    • http://salkim.com/userfiles/file/lubewibudevumipazorido.pdfIn PDF document text
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160869de9363b6---rivunoto.pdfIn PDF document text
    • http://melissajacksonmd.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c33983f7b6---18110294445.pdfIn PDF document text
    • https://www.inter-tube.co.uk/wp-content/plugins/super-forms/uploads/php/files/3227eb9a07af9d8f698f883715947817/tolepeladeduronazavovexul.pdfIn PDF document text
    • https://singaporeroadshow.com/wp-content/plugins/super-forms/uploads/php/files/b87ef667dbe1cd71e7528f5392b00f92/kukeparewalufabesileke.pdfIn PDF document text
    • https://www.hontoys.com.au/wp-content/plugins/super-forms/uploads/php/files/qi2peenav1bssifgon7k785a94/55018238319.pdfIn PDF document text
    • https://cffcommunications.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/1608668446ddfd---4818407151.pdfIn PDF document text
    • https://lashmakerpro.it/wp-content/plugins/super-forms/uploads/php/files/50ugounksrng6gbn9m90nvt531/tiguwedapopurijarodopolos.pdfIn PDF document text
    • http://halvani.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090b5b817f2e---zixige.pdfIn PDF document text
    • https://bravo-hk.com/userfiles/file/tofesesugofazafaw.pdfIn PDF document text
    • http://www.yoko-ono.be/images/userfiles/file/jikasuv.pdfIn PDF document text
    • https://cspdental.com/wp-content/plugins/super-forms/uploads/php/files/2cfcf0cd812c0aa6c823f17ebb233881/nivutit.pdfIn PDF document text
    • https://autoschiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a6eefcb74df---wivujexegezu.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607d6bb87ddc6---mivovu.pdfIn PDF document text
    • https://luminex.pl/upload/file/mufisolekewipal.pdfIn PDF document text
    • http://iaestedresden.de/userfiles/file/mowiliboliwamugexigo.pdfIn PDF document text
    • https://www.ibyservice.com/wp-content/plugins/super-forms/uploads/php/files/53f807301410b1f9c08a986481faa8dd/gosupezawe.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_off0000d76d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD76D 5188 bytes
SHA-256: 0db622e02a3130fdd8841ed460476631c350eba1fcb951589835f54373632492
font_01_sfnt_off0000e925.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE925 10856 bytes
SHA-256: 5b592b51a9395134768ef112286d11fa955e1be41576cdbac8941bca9dd6afdf