Malicious PDF — malware analysis report

Static analysis result for SHA-256 b39441e31012dbe6…

MALICIOUS

PDF

79.0 KB Created: 2021-06-29 19:48:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 421b442a1248dc6cd56804a5c702cc98 SHA-1: 58fc8e9122d43d3d31f367b76829c91246ca0fcc SHA-256: b39441e31012dbe60478c7e2e2135d6be6a4480ba450ef837c626c00d9352841
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous URLs pointing to compromised WordPress sites and other domains, suggesting it's used to redirect users to phishing pages or download further malware. The presence of multiple PDF link farm heuristics reinforces this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9958

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://archism.ru/uplcv?utm_term=donating+to+the+light+fable+2+zenith
    • https://www.costaverde.it/wp-content/plugins/formcraft/file-upload/server/content/files/160a46bb7bbca3---164016953.pdf
    • http://www.gametimecatering.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4b72525705---51351104727.pdf
    • http://olimpic.hu/ckfinder/userfiles/files/44446819727.pdf
    • https://deedpoll.sg/wp-content/plugins/super-forms/uploads/php/files/1f44064b9b4196329eff982978220bdb/kutegosisovukeniga.pdf
    • https://sharzh-ufa.ru/wp-content/plugins/super-forms/uploads/php/files/126a6aedcfeea8a0c0dd221c974aba7d/vupaduvunolujamopuxu.pdf
    • http://vorne-sitzen.eu/pcms/content/file/waxuxibelasunisos.pdf
    • http://kassa.pl/userfiles/file/kajaxowisosafupif.pdf
    • http://hillcountryawningsandsunscreens.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f8a14c9673---samuvolegilu.pdf
    • https://www.geosuiteonline.de/wp-content/plugins/formcraft/file-upload/server/content/files/16072ed2bafb83---78132036200.pdf
    • http://amy-tsai.com/images_express/userfiles/files/560763692.pdf
    • https://readxyz.org/wp-content/plugins/super-forms/uploads/php/files/2c4b5dcf109a6024f190057540ef44c0/kikukaxan.pdf
    • https://sy-tech.eu/file/47269357126.pdf
    • http://web68s.com/upload/files/gomogexolexexuzenag.pdf
    • http://dioceseofniranam.org/userfiles/file/80795090801.pdf
    • http://niestachow.pl/data/aktualnosci_imgs/file/36209352622.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083b6c671bb6---38052779008.pdf
    • https://sirikulsteel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e2ff0638d5---11074202229.pdf
    • http://2ds-creations.fr/userfiles/file/dokugimumeredakagodinus.pdf
    • http://www.stratcareerservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a2317899bc2---85110179702.pdf
    • http://www.petersmetalstitching.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1606f008f6abb5---83130029470.pdf
    • http://atthaya.com/file_media/file_image/file/kefeketofebu.pdf
    • http://www.inhd.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160947138f3377---69144401605.pdf
    • http://www.britocunhaadvocacia.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/16084673bd7e86---xoragegekupalowonagowo.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_off0000d275.bin
37e8f1268c24aecb77aec44a7fc5bd287694f14e4c9ee9cb487263f74b7aa3b1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD275 10548 bytes
font_01_sfnt_off0000ea7b.bin
7ba25de1fb4c058bccc0353ac0a66b8f4a17996448989d962a09acfe6fc71037
pdf-font-stream PDF embedded font (sfnt) at offset 0xEA7B 16916 bytes
font_02_sfnt_off0001168e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1168E 16792 bytes