Malicious PDF — malware analysis report

Static analysis result for SHA-256 993d7f4781308587…

MALICIOUS

PDF

74.0 KB Created: 2021-09-04 22:51:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: aeeaf5d4781f73ee7ede744ce7b3c94e SHA-1: 5b80b39070d9cae5058911707a64eb61b7417a7a SHA-256: 993d7f47813085875dd12e9af15132a01d5f5e763f982cf78bf12e6c1c954f9a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many pointing to compromised websites or disposable hosting, indicating a link farm designed to redirect users. Heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' strongly suggest this is a malicious lure. The ML classifier and ClamAV detection further confirm its malicious nature, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://laborke.ru/uplcv?utm_term=structure+of+an+argumentative+essay+pdf
    • https://denimder.org/resimler/files/zelijipitekejoduvuf.pdf
    • http://www.magicapro.it/wp-content/plugins/formcraft/file-upload/server/content/files/160acfba9711fb---70365385339.pdf
    • http://cka-shiba.com/ckfinder/userfiles/files/fizebezagoxezizevevejigi.pdf
    • http://ahxxzx.com/userfiles/202107/file/5939128713.pdf
    • https://www.plsok.com/wp-content/plugins/super-forms/uploads/php/files/84ada8940bd55b8c34abc0da5b458c0c/rinolebo.pdf
    • http://jeugdopdewetenschapsagenda.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160ecd479b02e4---walimemokuromiwowagozujoj.pdf
    • https://www.pharmaright.ca/wp-content/plugins/super-forms/uploads/php/files/hn5c0roug4s01cq8e9am3srt7u/lupopipadubuzawuzuxefato.pdf
    • http://hyundaidongdo3s.com/images/files/zatejajuvijiza.pdf
    • https://brunoamaranti.it/wp-content/plugins/super-forms/uploads/php/files/1okehmfadiffefme1tvs3v4b13/10013541997.pdf
    • https://unosms.us/userfiles/file/74793284257.pdf
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607d0ae71d989---17271259424.pdf
    • http://technocom.pl/editor/file/54303107813.pdf
    • https://afayl.com/userfiles/file/bixujuzumaputo.pdf
    • https://phase1acoustics.com/wp-content/plugins/formcraft/file-upload/server/content/files/16097477499901---30898460596.pdf
    • http://xecuoihuyhoang.com/uploads/userfiles/file/87763958151.pdf
    • https://tramtron.vn/uploads/files/files/tajugokuroxemomujozul.pdf
    • http://c2mag.com/wp-content/plugins/formcraft/file-upload/server/content/files/160751003a4098---93706423408.pdf
    • https://ags-car.com/upload/files/36174573072.pdf
    • http://geology.ie/wp-content/plugins/formcraft/file-upload/server/content/files/160864eb3b1204---xezakalixijuge.pdf
    • https://repare-ton-smartphone.com/userfiles/file/59247060812.pdf
    • http://serdceprirody.ru/userfiles/file/dozotozelamevesozi.pdf
    • http://baigeleather.com/userfiles/file/17070866928.pdf
    • https://udachi.co.th/wp-content/plugins/super-forms/uploads/php/files/5vre9l0uhh3sg0dirkgnk7p28e/62163882030.pdf
    • http://architettoletiziamasciotta.eu/userfiles/files/jegujumubidirov.pdf
    • http://aprendanow.com/wp-content/plugins/super-forms/uploads/php/files/d4792fefe31e97d889a393b9d3bc631d/jejigodamuzuxadikofi.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_off0000bd8e.bin
c620581aa3544b903d925d4429dacd5e08d5dce211bd2b6c8797fe9ed11939ad
pdf-font-stream PDF embedded font (sfnt) at offset 0xBD8E 11272 bytes
font_01_sfnt_off0000d7e2.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD7E2 16792 bytes
font_02_sfnt_off0000eff4.bin
d0d77d8390858359ba7ee2c33bc6c54478034aeda2ec6cc598d95ecdc10cd305
pdf-font-stream PDF embedded font (sfnt) at offset 0xEFF4 16544 bytes