Malicious PDF — malware analysis report

Static analysis result for SHA-256 8a9ca2c6990f9a81…

MALICIOUS

PDF

76.1 KB Created: 2021-06-14 19:37:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-01
MD5: 2a5b4f99bdb1e4dbfe5bd4b2c6bb5b54 SHA-1: 1c5e28d2526b907745daa2e695b0ff93ceac4696 SHA-256: 8a9ca2c6990f9a81f9a460622da7d4ff3d25006543e77d8ccbe55fb876b40477
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://krisoc.ru/uplcv?utm_term=10th+tamil+guide+pdf+free+download+2020 PDF link annotation
    • https://ceadersvalet.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4d3eab36ec---kawopekokitulo.pdfIn PDF document text
    • https://hmv.ir/wp-content/plugins/formcraft/file-upload/server/content/files/160b2a19953f5a---22434405908.pdfIn PDF document text
    • http://conwaychristian.org/wp-content/plugins/formcraft/file-upload/server/content/files/16071e3927efc5---xetusug.pdfIn PDF document text
    • http://dush-kz.ru/uploads/fck/file/xuxatowusi.pdfIn PDF document text
    • https://arrayamed.com/userfiles/file/29844074938.pdfIn PDF document text
    • https://asiaviews.org/wp-content/plugins/super-forms/uploads/php/files/o74b46e5sas0d7nk3tiilogif2/gobuperapido.pdfIn PDF document text
    • https://www.mozartcantat.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16092514f40562---62971119968.pdfIn PDF document text
    • http://mouaumfb.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c14ce0a5f99---57671913808.pdfIn PDF document text
    • http://ridendo.cz/files/file/mowuvupaxatak.pdfIn PDF document text
    • https://www.superioreagle.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085f86f74c9a---93987597650.pdfIn PDF document text
    • https://smoothnomad.com/wp-content/plugins/super-forms/uploads/php/files/sr76q9ldqmaru9mjldut6i6oj3/ditifizukedepapa.pdfIn PDF document text
    • https://haps.company/wp-content/plugins/super-forms/uploads/php/files/juepnknibhj8nbjhl8v7mgd317/37196060641.pdfIn PDF document text
    • https://www.picmephotoboothhire.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1609e06c3d4074---sakikuvetagemetitafe.pdfIn PDF document text
    • https://quickonboarding.com/wp-content/plugins/super-forms/uploads/php/files/a398eeecce06ec2915c3a2235ebbf29f/futowimi.pdfIn PDF document text
    • https://familienarbeit3plus.ch/userfiles/files/42750303522.pdfIn PDF document text
    • https://g-ortho.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160839618db0c9---gijizopel.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_off0000ec64.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC64 5600 bytes
SHA-256: 10982389141df0ea67f42526ad12e8f8dd736286ccf9432ca948cc3d4355dedf
font_01_sfnt_off0000ff5d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF5D 10532 bytes
SHA-256: d8677a20e73d96f5df2cc863fcf63de40780ea918b5d9afd50b576ce5be3439e