Malicious PDF — malware analysis report

Static analysis result for SHA-256 6c49c13551e948ef…

MALICIOUS

PDF

83.6 KB Created: 2021-09-03 23:49:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: a9333f3bf4f457296ef706b6e386be0a SHA-1: 632189e22c4ffa6dc674b872d7472c707cb57ec3 SHA-256: 6c49c13551e948efe16184d094952ef1e38f88491979f96c8169d867706fff85
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to compromised WordPress upload storage and other disposable hosting, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://nowackleverkusen.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c7416537034---kobijufaxelul.pdf In PDF document text
    • http://sys-svinding.dk/userfiles/file/matatowudowelez.pdfIn PDF document text
    • http://metzpaintings.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c47dba29eb5---57595999814.pdfIn PDF document text
    • http://wsm.hk/images/files/96555141357.pdfIn PDF document text
    • http://parcroyale.hk/userfiles/44003757785.pdfIn PDF document text
    • http://wingmanresearch.com/userfiles/files/bipelimis.pdfIn PDF document text
    • https://rrvchefs.com/wp-content/plugins/super-forms/uploads/php/files/79a6b0a766cf6fc1b68b47c3fe63e14c/saxudaxafofurijised.pdfIn PDF document text
    • https://www.nstoplana.rs/ckfinder/userfiles/files/wafoxavasekuge.pdfIn PDF document text
    • https://qian-ho.com/upfiles/editor/files/42543123863.pdfIn PDF document text
    • https://visionbrindes.com/admin/fckeditor/userfiles/file/23930456186.pdfIn PDF document text
    • http://nemdanangpho.com/uploads/2021-08-18/images/files/88378147016.pdfIn PDF document text
    • http://tunglamgarden.com/images/fck/file/53998501003.pdfIn PDF document text
    • http://aire-limpio.com/img/editor/file/76368303738.pdfIn PDF document text
    • https://gmonlinestore.com/wp-content/plugins/formcraft/file-upload/server/content/files/16124d4309f9a1---tajiparixolarawadakaxiren.pdfIn PDF document text
    • http://deleeuwputten.nl/site/data/ws/files/22619771661.pdfIn PDF document text
    • https://robertmatzuzi-massagetherapist.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160b7516145936---luvex.pdfIn PDF document text
    • http://etoprosto.ru/ckfinder/userfiles/files/tonudukiwojewisiweto.pdfIn PDF document text
    • http://ghalemdi.com/userfiles/file/gijadudineruwim.pdfIn PDF document text
    • http://atya.eu/files/file/naxokozuvusozetirisixewag.pdfIn PDF document text
    • https://zoomkish.com/basefile/zoomkishcom/files/dolesinaniwemikirafakozub.pdfIn PDF document text
    • http://anhuizhkj.com/upload_fck/file/2021-9-3/20210903132500782264.pdfIn PDF document text
    • https://interesttour.com/wp-content/plugins/super-forms/uploads/php/files/87dc46e3cb6ef96a634efb376b41c5b6/62144540692.pdfIn PDF document text
    • http://www.veronicaneal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/160e4a78864d09---26821439536.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=falling+in+love+with+you+piano+sheet+music+pdfPDF link annotation
    • 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_off0000dd4f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD4F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f566.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF566 11312 bytes
SHA-256: 162204a2db4539b55a1a81bc3cd2088d6847e892faeecff90d5ca760fcc7f0c1
font_02_sfnt_off00010faa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FAA 18396 bytes
SHA-256: 01153dd48bddffe7d112214d532ab0cfa2ea1e77ce798f484d17e2d2a9aa5748