Malicious PDF — malware analysis report

Static analysis result for SHA-256 b943c16e5197f1a5…

MALICIOUS

PDF

94.1 KB Created: 2021-06-28 06:50:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: eab1755cc3ff3b512a9581e225e36547 SHA-1: 83b8c556e36a83e0ec3bd26706dfc5462a4529b2 SHA-256: b943c16e5197f1a55728b03595f824df475f4d813cbc62ebb20eab1f438204d8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous external URIs and links to compromised CMS upload storage, indicating it functions as a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9820

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://krisoc.ru/uplcv?utm_term=lois+griffin+saying+peter
    • https://angkortaxiservice.com/userfiles/file/roxosawoxadewotijozoxopuk.pdf
    • http://asu.com.vn/wp-content/plugins/super-forms/uploads/php/files/0e6472rqigvedl3008li02oral/sudozalafuvixizogozax.pdf
    • http://kyanite.tv/userfiles/file/nazigiset.pdf
    • http://sushinamu.com/uploads/files/19959751192.pdf
    • https://theelementrama9.com/userfiles/files/37353521387.pdf
    • http://pansophers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f64b438c59---84588447114.pdf
    • https://www.jscorporation.co.in/wp-content/plugins/formcraft/file-upload/server/content/files/160949171aa2a9---18004608410.pdf
    • http://vom-ragnaroek.de/uploads/file/54286195284.pdf
    • http://www.optionassurance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16078c7fcd9830---31635251885.pdf
    • http://lushexperiences.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a14bb203088---63295176004.pdf
    • http://djapm.com/userfiles/file/34941260606.pdf
    • https://www.themeshcowork.com/wp-content/plugins/super-forms/uploads/php/files/c1fabb2d451ef9460f0e0eef244eb806/15786966788.pdf
    • https://gpuhub.net/wp-content/plugins/super-forms/uploads/php/files/qhldcm8c4r0esvqe5mug2inm70/zazubewozekaxux.pdf
    • http://almar-bus.pl/userfiles/file/xutetajogorujot.pdf
    • https://www.accidentinjuryalbuquerque.com/wp-content/plugins/super-forms/uploads/php/files/qndqardnp76bl6n4pe5ekkhc3h/motalijogubilewosubap.pdf
    • http://originalcheck.it/public/img_admin/file///saniluwofivibo.pdf
    • https://mebelpozakazu.ru/wp-content/plugins/super-forms/uploads/php/files/a64dc0351d952be3f9857c0553fe0769/45739449128.pdf
    • https://usssecuritate.ro/userfiles/file/kuvifogirogokutepova.pdf
    • https://gbagencement.fr/uploads/file/kutanuxapamugaw.pdf
    • http://teusz.pl/UserFiles/file/xoraxuvexanid.pdf
    • http://france-ex.com/images/blog//file/58739020565.pdf
    • https://www.marvistasales.com/wp-content/plugins/super-forms/uploads/php/files/2060a3fbae629182f7877bed6224818a/vapokemirojofokoxeri.pdf
    • https://ddriu.hu/wp-content/plugins/super-forms/uploads/php/files/bb08c98c54c827b3cd2c621127dc6242/zavexumutis.pdf
    • http://shuimotongyuan.com/userfiles/file/38925069214.pdf
    • http://anhuishangbiao.com/upload_fck/file/2021-5-5/20210505015232621242.pdf
    • https://embassyinvietnam.com/webroot/img/files/26123880942.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_off00010da1.bin
1e47a79fca01dfb0e988e6a78ff6630218f071ef6b4181e199b75f4338419b3c
pdf-font-stream PDF embedded font (sfnt) at offset 0x10DA1 10556 bytes
font_01_sfnt_off000125df.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x125DF 16792 bytes
font_02_sfnt_off00013df1.bin
77069e6c39d537fe7eac8f473e313bcbadb4271129331d6c7ffd2bc3f7a27238
pdf-font-stream PDF embedded font (sfnt) at offset 0x13DF1 17356 bytes