Malicious PDF — malware analysis report

Static analysis result for SHA-256 4bd831a80deb4be5…

MALICIOUS

PDF

88.3 KB Created: 2021-08-09 08:27:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4aa17e65a0dcf1b0ed2e93dc5f196636 SHA-1: 0150a5221a60573c0817080ee01b43fda3bb9216 SHA-256: 4bd831a80deb4be5a254f53782de4733c01a56c5503651b5aed6f3b75db0af38
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress sites, suggesting a phishing or malware distribution campaign. The ML classifier and ClamAV detection strongly indicate malicious intent. The presence of multiple external URIs and link farms points towards an attempt to lure users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://cructi.ru/uplcv?utm_term=free+download+mp4+movies+hindi+dubbed
    • http://steakclubhn.com/campannas/file/80772774830.pdf
    • http://sad-azov.ru/wp-content/plugins/super-forms/uploads/php/files/9ff834651c644cae68817a867e076ed2/82121734589.pdf
    • http://kraljicabih.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b1bcbe63559---minewubevifilemida.pdf
    • http://c2mag.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c6de4d814f---79163626018.pdf
    • https://www.ideaklinikkadikoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ba215d8456b---15657559362.pdf
    • https://www.alpha-dynamics.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160a5b47cd404e---17381467799.pdf
    • http://sieckultury.pl/wp-content/plugins/super-forms/uploads/php/files/7c8372fa74b7349193699eb28f8e3644/97704504040.pdf
    • https://nmg.lv/img/uploads/files/25832733680.pdf
    • http://faradtvandor.hu/picture/userfiles/file/nogufex.pdf
    • https://loskutova.site/wp-content/plugins/super-forms/uploads/php/files/c8abb09013f19760832ea26a18d786cb/77868596757.pdf
    • http://xn--b1ahhafccpgkb2bxo.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/d6ff6214693414b316ba2403c0bc9589/16580372911.pdf
    • https://www.davidwoodpersonnel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073bcd3a3c76---53949519826.pdf
    • https://www.lang-mayer.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607fd9fca3a50---35739763763.pdf
    • https://myphi.biz/nbloom/fckuploads/file/pozirifuwekiwalojo.pdf
    • http://daikinhbac.com/upload/files/lotinorofabumitopiturekig.pdf
    • http://ctmmaximoravenna.com/ckfinder/userfiles/files/vemifow.pdf
    • http://theopenhouseclub.com/wp-content/plugins/super-forms/uploads/php/files/666ec3fb22f52e46d455300ec3501f08/19227165553.pdf
    • https://www.hdcorp.com.br/wp-content/plugins/super-forms/uploads/php/files/d7a9tkffip9r3n8opoiqsjfoot/78402469531.pdf
    • http://www.awakohchang.com/image/upload/File/5059586945.pdf
    • http://www.mearesandassociatesllc.com/siteuploads/editorimg/file/ludiwuxomademizag.pdf
    • https://www.idahomedia.com/wp-content/plugins/super-forms/uploads/php/files/d3237f69451d77e345b5191b35e0facd/takuputu.pdf
    • http://icmasistemas.com/userfiles/files/mulosov.pdf
    • https://canionglobal.com/FCKeditor/file/rupemajovudos.pdf
    • http://etyekilovarda.hu/userfiles/file/vorigafojib.pdf
    • https://xn--interpeas-r6a.es/upload/files/kobekoponuzubogaxavaxa.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_off0000f531.bin
c3d64c591b57eae16ddcd4abd43483722a0565382a0dbbab5c58d8d214465eb2
pdf-font-stream PDF embedded font (sfnt) at offset 0xF531 17100 bytes
font_01_sfnt_off000121e8.bin
f6bb9796b34bdbdbcb321ad400d30f2609ec093fc32bda10581f14e187641caa
pdf-font-stream PDF embedded font (sfnt) at offset 0x121E8 11008 bytes
font_02_sfnt_off00013b1a.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13B1A 16792 bytes