Malicious PDF — malware analysis report

Static analysis result for SHA-256 4a0289b83d575ba3…

MALICIOUS

PDF

129.8 KB Created: 2021-10-07 18:48:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0c6ad8eea04aede76348be9fedbe95d0 SHA-1: 7a6485da547ae41b65c648d8de9dba5f9afd85e0 SHA-256: 4a0289b83d575ba366fa888a6017b4e53728f4cb063f4e3cbe06a24736dfb8bf
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links to external websites, many of which are hosted on potentially compromised or disposable domains, suggesting a link farm or phishing lure. The presence of PDF-specific heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' further supports this, indicating the document's primary purpose is to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9828

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 http://antwerp-rentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/161511ab3d5177---66327222641.pdf
    • https://testgit.begurholidays.com/uploads/userfiles/files/61952095276.pdf
    • http://newworldss.com/uploads/file/gebotefes.pdf
    • https://www.ccs-corporation.com/ckfinder/userfiles/files/pifukubawerudagi.pdf
    • http://lycee-elm.org/userfiles/file/levesulejoxof.pdf
    • https://dichvuketoansg.com/luutru/files/31073842811.pdf
    • http://jca-t.com/fck_image/file/3095083327.pdf
    • http://atem.sciara.eu/public/upload/file/vovekatajimofojenavixafo.pdf
    • http://bionazorat.uznature.uz/userfiles/file/11054078311.pdf
    • http://bouwbedrijfbouwheer.nl/userfiles/file/forejinuxagafuzobin.pdf
    • http://hightopeducation.com/cms_uploaded/file/vixifafimofozobulaxip.pdf
    • http://architettosirocco.it/userfiles/files/davisalenatetezul.pdf
    • http://cameranichietsu.com/luutru/files/3879642974.pdf
    • http://xn--k1akb4c.xn--p1ai/userfiles/file/43722611309.pdf
    • http://freeski.hu/freeski/file/xuziku.pdf
    • http://hungthanhauto.com/luutru/files/52701269870.pdf
    • https://ochronaskory.pl/pliki_user/File/65568784538.pdf
    • http://gemcom.org/userfiles/file/7318656382.pdf
    • https://el-tall.pl/pics/file/tuxibitari.pdf
    • http://kingtonkatsu.com/uploads/files/nupefuvav.pdf
    • http://budka39.ru/files/68491128489.pdf
    • http://www.norestim.ro/wp-content/plugins/formcraft/file-upload/server/content/files/161306a97919c1---16196528985.pdf
    • https://smarttactic.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1614502a9d77be---viledoxidelizalivojobug.pdf
    • http://dakdekkersindex.nl/images/uploads/46108543473.pdf
    • https://jin-ji.com/upload/files/vujoboje.pdf
    • http://www.w.radeton.cz/ckfinder/userfiles/files/dejexowi.pdf
    • https://xn--90aweabvm.xn--p1ai/ckfinder/userfiles/files/xijekawozupamarinir.pdf
    • http://cdkuysuujk.handysociality.com/upload/files/42738405292.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=statement+of+purpose+for+phd+in+physics+pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00019041.bin
8d3ec8d6d6a6b74dc6a24b260b38e954391323adb42a9e3338e276d42020faf5
pdf-font-stream PDF embedded font (sfnt) at offset 0x19041 11128 bytes
font_01_sfnt_off0001aa0e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1AA0E 16792 bytes
font_02_sfnt_off0001c220.bin
098f2899ec63870fd8e2356667b30726585fe673990e989f7b8564f77ef83931
pdf-font-stream PDF embedded font (sfnt) at offset 0x1C220 21476 bytes