Malicious PDF — malware analysis report

Static analysis result for SHA-256 b8b4e65a5cf55b80…

MALICIOUS

PDF

77.6 KB Created: 2021-06-30 20:34:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7767bc2555777cf4e6dc32ae6bdb92e4 SHA-1: 0bfc539925a8597eefb2fbaf69a2d0e1d6b1d73f SHA-256: b8b4e65a5cf55b806aee21f2bb08961e3b2c2856eaca99458aecf76470ac04ca
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Heuristics identified the document as a link farm pointing to compromised WordPress upload storage, suggesting it's used to host malicious files. The presence of multiple unknown URLs further supports its role in distributing malware or phishing content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/160714085c10c3---putonizijed.pdf
    • http://yokohama-model.com/userfiles/files/xajugasipejejigavixiw.pdf
    • http://101-games.ru/images/uploads/files/wogipelofe.pdf
    • https://broadstripe.com/wp-content/plugins/super-forms/uploads/php/files/2c4d23422af75189418aa0b781178fd1/wumujozapojogixonuwefule.pdf
    • https://socialchangefactory.org/wp-content/plugins/super-forms/uploads/php/files/7fd470eba643c149184e22d88c75fb4a/japorovav.pdf
    • http://www.reroofingbrisbaneqld.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16080a26439383---nuruwadoxuxiku.pdf
    • https://sellerflows.com/wp-content/plugins/super-forms/uploads/php/files/cadac32a7896d7215692d9d1fac9b5a6/12638007475.pdf
    • https://beytarimcilik.com/admin/editor_resim/file/nerasufo.pdf
    • http://biotop-zamosc.pl/userfiles/file/fumodifuwagusovateke.pdf
    • http://granite1962.com/clients/869125/File/xamexupagijuwajokofosixo.pdf
    • https://hotelritariccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/160a3884aab234---panonixuvabuvaforavowag.pdf
    • http://myshopekerala.com/userfiles/file/pikikolizipijapibolataw.pdf
    • http://joshuadacosta.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089bc3c49fbf---xikapamov.pdf
    • http://peggylittlelawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/penosiluxotatejogowa.pdf
    • https://hoffmanowska.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1607f9264848e4---82856060823.pdf
    • http://dragonera.cn/admin/userfiles/file/43534808529.pdf
    • https://hsegroup.ru/wp-content/plugins/super-forms/uploads/php/files/8l2d5auqc4md3lk6rl1lii9eq7/55446890164.pdf
    • http://homestationrealty.com/userfiles/files/44334828873.pdf
    • http://goldenbaycruisesagent.com/userfiles/file/15596157824.pdf
    • http://vector-luczak.pl/new/fck_user_files/file/pesixigup.pdf
    • https://husvagnsexpo.se/wp-content/plugins/formcraft/file-upload/server/content/files/1606cda196e101---deguwewu.pdf
    • http://arunimaflavours.com/userfiles/file/37720419211.pdf
    • https://torrentclub.vip/wp-content/plugins/super-forms/uploads/php/files/s701vvstevlm511m59ijp0s05d/81092405644.pdf
    • https://trsbarriersdirect.com/wp-content/plugins/super-forms/uploads/php/files/rqq4kfqmjq7feqqgj952mtkqvv/nexoxezakelubifege.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=contractions+18+weeks
    • 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_off0000cb42.bin
36d475523ee7205161c10e946428411a8e1252425828cbd5ad7f1eccfe32451a
pdf-font-stream PDF embedded font (sfnt) at offset 0xCB42 17288 bytes
font_01_sfnt_off0000f886.bin
26358e6095a4baede6c8270fc4221fb8e2ecdab0ec16c4049f86de6dcc0ab337
pdf-font-stream PDF embedded font (sfnt) at offset 0xF886 10648 bytes
font_02_sfnt_off0001113a.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1113A 16792 bytes