Malicious PDF — malware analysis report

Static analysis result for SHA-256 a531b2cd42b67b39…

MALICIOUS

PDF

69.1 KB Created: 2021-09-27 03:56:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: f2fbcfed6d71215fb57f1553048f6af0 SHA-1: bb4709dd36bdb53835c6a5f79918bb98736e56a8 SHA-256: a531b2cd42b67b392bba9b18b57634236c08952ba6c17f9179b17a6720fcc214
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous external URIs and links to compromised CMS upload storage, suggesting it functions as a link farm to distribute malicious content or phish users. No scripts were extracted, but the PDF structure and URL patterns are indicative of a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 https://huntic.ru/uplcv?utm_term=how+to+mobile+games+on+pc PDF link annotation
    • https://mithermomix.com.mx/wp-content/plugins/super-forms/uploads/php/files/f9fa0a1ef4fc438435781bd070ed1b5b/nejoturidipuzugi.pdfIn PDF document text
    • https://trucraftsmanship.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c505bbae61---20537612652.pdfIn PDF document text
    • http://dfwsedan.com/nbloom/fckuploads/file/zipugerarivolupixi.pdfIn PDF document text
    • http://acm-medicali.it/userfiles/files/xutenonojekoladejegi.pdfIn PDF document text
    • http://goozzl.com/userfiles/files/40605738893.pdfIn PDF document text
    • http://fuzoku-kyujin.jp/ckfinder/userfiles/files/xitiketivatabojadefukuziz.pdfIn PDF document text
    • https://securitydm.net/slicice/file/dowiwolekariroja.pdfIn PDF document text
    • http://mgtuae.com/uploads/file/nebewedisaguvel.pdfIn PDF document text
    • http://sentezetutmerkezi.com/upload/ckfinder/files/91461188883.pdfIn PDF document text
    • http://smartwealthhk.com/userfiles/3469465817.pdfIn PDF document text
    • http://hatdesechia.com/storage/ckfinder/files/89330388260.pdfIn PDF document text
    • http://adimhukuk.com/resimler/files/zaluse.pdfIn PDF document text
    • https://doanandieuduong295doson.vn/namthuan/images/news/files/43226128653.pdfIn PDF document text
    • http://chinhsuasolieu.com/media/files/teluxuk.pdfIn PDF document text
    • http://bobmeetin.com/media/galleries/files/15275491376.pdfIn PDF document text
    • http://sva-jeanroze.com/xmedia/file/9753658786.pdfIn PDF document text
    • http://remontnoedelo.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1614639a362a85---79423254764.pdfIn PDF document text
    • https://medsplus.us/admin/images/file/lusurupukijoxagozir.pdfIn PDF document text
    • http://videofilm-tv.ru/content/File/38525973648.pdfIn PDF document text
    • https://livstyle.ro/home/livstyle/public_html/uploads/files/58611943860.pdfIn PDF document text
    • http://straub-online.ch/userfiles/files/83976359211.pdfIn PDF document text
    • https://zniczekowalczyk.com/user_images/file/51929580103.pdfIn PDF document text
    • https://canevastoilestjean.com/upload/editor/file/84423652421.pdfIn PDF document text
    • http://nesemlak.com/test/images/uploads/files/rijupoxi.pdfIn 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://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_off0000af2c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF2C 15444 bytes
SHA-256: ad7d85b13a81be1241ee9bb28bb75f034948e72761fec8cf5783c01c40292bb4
font_01_sfnt_off0000d64a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD64A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ee61.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE61 10832 bytes
SHA-256: 3582d889b09d74e4cef9d7dbe592741940fb07ec31d05c1dd8ae2c8e0e88a2b0