Malicious PDF — malware analysis report

Static analysis result for SHA-256 903f4576f14d3958…

MALICIOUS

PDF

68.5 KB Created: 2021-05-15 11:22:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 3bdc0197f17ca63d59e0d06fad91262b SHA-1: 2013ad0c53c9faa11b7a5d2cfe2e79306fbf2098 SHA-256: 903f4576f14d39581165b83482923b8206f7a3a1790a0cce105cfb05ec9af9b1
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple compromised WordPress sites, likely intended to trick users into downloading malicious files. The ML classifier and ClamAV detection strongly indicate malicious intent, with the latter identifying it as a phishing trojan. The presence of numerous external URIs and compromised CMS upload links supports the conclusion that this document is part of a phishing campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://famcareconnect.org/wp-content/plugins/formcraft/file-upload/server/content/files/16097d5523d6ee---gowudanuvijoxorolimow.pdf
    • https://mandalaconfeccao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160754bce1b590---82355798628.pdf
    • https://theshairpodcast.com/wp-content/plugins/super-forms/uploads/php/files/f1677edda180b5347511b2ebf8e288d5/40651172740.pdf
    • https://laser-arena.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1606e461337d08---69239363422.pdf
    • http://automotiveenergy.cz/userfiles/file/63016258826.pdf
    • http://juniorsmagazine.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078d206572c4---loxobo.pdf
    • http://shmountaineering.co.uk/wp-content/plugins/super-forms/uploads/php/files/sii8q5h0i7psvng3piug6g0ee2/84702837641.pdf
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/vu1k4ljath10fblv1ct0hc5nk2/wijojewitememivis.pdf
    • http://www.jesuseslaroca.org/wp-content/plugins/formcraft/file-upload/server/content/files/16077739aec6c8---titifi.pdf
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/qgmab4m0gm76r1t82agg82tq2q/52250421077.pdf
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/16078983056305---vewupulorok.pdf
    • https://inchiriereelicopterromania.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160917edb19abd---92538739328.pdf
    • https://glass-haus.ru/wp-content/plugins/super-forms/uploads/php/files/797064f3a005298b02d94600183aafa1/dolopovaxokivi.pdf
    • https://alignerco.com/wp-content/plugins/super-forms/uploads/php/files/d328aa1f9aaf5bcc720bd23511579687/83319061476.pdf
    • https://storage-in-motion.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079a48be86a3---12763997465.pdf
    • https://centar-znr-zop.hr/wp-content/plugins/formcraft/file-upload/server/content/files/16073b7c25818c---4838725895.pdf
    • https://webmodeli.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f874f4c597---76883228164.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=jurassic+park+builder+mod+apk+update
    • 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://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cf69.bin
6a094a93be4011278bea00808a4c3b884fd2250f0d10bcfd8f052077212430fd
pdf-font-stream PDF embedded font (sfnt) at offset 0xCF69 5412 bytes
font_01_sfnt_off0000e1b8.bin
9d05e054feb8d2d35f2467f4b6c0fab8aeb4b8c548b3d554b372e5645190d0ff
pdf-font-stream PDF embedded font (sfnt) at offset 0xE1B8 10468 bytes