Malicious PDF — malware analysis report

Static analysis result for SHA-256 221e320dc9834102…

MALICIOUS

PDF

90.0 KB Created: 2021-08-06 06:56:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1ffb58972939a68f3e912f13bf79a6c9 SHA-1: 462bcf8b44324d138c0a6d120c187429d1fac5c4 SHA-256: 221e320dc98341026b7607a776c686b49165111446e0c2e607f5dcdf1c0e1d26
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and numerous external URIs, many of which point to compromised CMS uploads and disposable hosting, forming a link farm. The ML classifier strongly indicates maliciousness. The embedded JavaScript likely facilitates the redirection or further payload delivery, contributing to the overall malicious intent of the document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 6

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://asiquim.com/ckfinder/userfiles/files/napejevuwelok.pdf
    • https://mmszke.hu/files/file/naxevavovevanaxudigapel.pdf
    • https://acryl-bg.com/userfiles/file/35733816130.pdf
    • http://www.ujepites.hu/userfiles/files/32847669620.pdf
    • http://imaginove.eu/data/Files/10721852553.pdf
    • https://arenda1s.ru/wp-content/plugins/super-forms/uploads/php/files/a56ccedd945f7f0fbd71fd5dab8d1e85/xudalibutopidejuf.pdf
    • http://1137.jp/app/webroot/js/ckfinder/userfiles/files/suwoxisam.pdf
    • http://thuephotocopytaihanoi.com/upload/files/16684329392.pdf
    • http://www.prunay-en-yvelines.fr/ckfinder/userfiles/files/70517341174.pdf
    • http://fogathajtohirek.hu/fckfiles/file/pofizipi.pdf
    • https://n-zvuk.ru/upload/file/dejifi.pdf
    • https://123kozijnofferte.nl/wp-content/plugins/super-forms/uploads/php/files/48b6tj18ar500btnf3g96180r3/vulogewagowibeju.pdf
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/1609fcae11fe1e---26280299211.pdf
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/v7vk2ktgtfeva2t3sslfojscpt/58806756463.pdf
    • https://privatecambodiatour.com/userfiles/file/suzizipuxilajelakug.pdf
    • http://totalfinance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16084ae445b584---54436069022.pdf
    • http://rentbucharest.net/images/userfiles/dusukinowegodasu.pdf
    • http://zae.me/datafiles/file/17579705738.pdf
    • http://rowanfamilyreunion.com/clients/28915/File/52796881276.pdf
    • http://salkim.com/userfiles/file/lexanidozakoxoj.pdf
    • http://www.cargeacrew.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607f6ab358c49---72505269507.pdf
    • https://www.hungryalex.com/wp-content/plugins/super-forms/uploads/php/files/sirkh1n75u8dppm9k198ocmkth/43583150917.pdf
    • http://www.goataxiservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072b40bc8a99---dikamuxolobulorewaf.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=how+to+cook+stouffer%27s+lasagna+in+toaster+oven
    • 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_off0000f75f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF75F 16792 bytes
font_01_sfnt_off00010f76.bin
63b8e2dcf86a40e74cf084c0e65cd6307599862849d054d805e32814676f3d87
pdf-font-stream PDF embedded font (sfnt) at offset 0x10F76 10880 bytes
font_02_sfnt_off000128d8.bin
bf3d6df29776bfd3c0f942c04fb8b2c49e4cf4bff996cba887497870c8a46989
pdf-font-stream PDF embedded font (sfnt) at offset 0x128D8 18712 bytes