Malicious PDF — malware analysis report

Static analysis result for SHA-256 37b16a160f4a12b7…

MALICIOUS

PDF

87.4 KB Created: 2021-07-29 12:43:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1cf9cfdcd4e2fd77a0082c646a32128a SHA-1: 9d5c344907383a59d26544922378465470f6f634 SHA-256: 37b16a160f4a12b7b102843f78ecded82e093ead51f7c92265fe764f9763b00f
156 Risk Score

Malware Insights

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

This PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains a link farm pointing to multiple compromised WordPress sites, indicating an attempt to redirect users to malicious content. The presence of embedded URLs and the nature of the heuristics suggest it is designed to exploit users by directing them to potentially harmful external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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 http://lichnyiybrand.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160be786abd2c4---90476399833.pdf
    • http://www.champcaregivers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160802e57c49d9---dadakupojadifusunivod.pdf
    • https://investmentskillsgroup.com/images/userfiles/file/71352319211.pdf
    • https://ethiquedevelopers.com/wp-content/plugins/super-forms/uploads/php/files/bea96f84f9c7e8399430a897f842d556/sazaboxirivilifuxed.pdf
    • https://autotrilogy.com/wp-content/plugins/super-forms/uploads/php/files/4e0a4428cfde7dba8af2f5630e5e57c3/jevinovivibutozokinu.pdf
    • http://www.chinahkcarplate.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cd286bd4de---taperurevobexunipobomev.pdf
    • http://ronniejoymemorialfund.com/clients/1/1a/1a75100f29d804137a154ca93ef51a80/File/20566489695.pdf
    • http://allamericannursing.com/userfiles/file/9525102757.pdf
    • http://yuha.be/_files/file/32224469728.pdf
    • http://phuocthuan.vn/images/pic/file/74531195337.pdf
    • https://holocaustresearch.pl/nowy/photo/file/14515457144.pdf
    • http://dafangtour.com/fckeditor/userimages/file/kepalozamiseb.pdf
    • https://agilitynd.com/wp-content/plugins/super-forms/uploads/php/files/0b35a8cf3ac9937231b8b28ef1af7795/xisakakajalozejijazatopaz.pdf
    • http://www.fullertherapy.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098cf326502c---gitebabunawabakopudife.pdf
    • http://wearebryants.com/clients/3/3b/3bb22ab34fb8fe691aabc4d0498f9caa/File/34784131631.pdf
    • http://indecomavo.pl/inc/67648311336.pdf
    • https://northstarexecutivesearch.com/wp-content/plugins/super-forms/uploads/php/files/55d1ed632875da578a482d1fd46b7989/tedisam.pdf
    • http://www.inhd.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c5251d8e15f---69656780140.pdf
    • https://globalclassic.org/wp-content/plugins/super-forms/uploads/php/files/qjdbco7uujhl9f6ne7h4shdt9o/vomoretudazisetigobigo.pdf
    • https://voyageaventurenepal.com/upload/files/67420102388.pdf
    • http://nextgt.eu/uploads/file/7592365039.pdf
    • https://bettenbaehren.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608dfd61dade6---duzidaluv.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=how+do+i+reset+my+daikin+remote
    • 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_off0000f553.bin
8dd02ed84f053063ec1d2f0bdda0d250d3a66ce9356e616bc79d98fa41d101e9
pdf-font-stream PDF embedded font (sfnt) at offset 0xF553 16360 bytes
font_01_sfnt_off00011f97.bin
7797693530cd0e8486d47c0f07d7ba2f318aa8623cfac606604a00ee40c945bb
pdf-font-stream PDF embedded font (sfnt) at offset 0x11F97 10648 bytes
font_02_sfnt_off00013805.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13805 16792 bytes