Malicious PDF — malware analysis report

Static analysis result for SHA-256 d1b0d91773457a6c…

MALICIOUS

PDF

85.3 KB Created: 2021-06-30 15:48:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 1a84df5845e670fffe61ffcb2fbbd2bb SHA-1: 5ab1a66fe45bfdf8a6996b280e8448295d02ef12 SHA-256: d1b0d91773457a6ca07489423f04d409a540c1af961752190e44321c2f11a4b1
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, which is a common technique for executing malicious code. It also features a link farm pointing to multiple distinct hosts, many of which appear to be compromised WordPress sites hosting similar PDF files. This suggests an attempt to distribute malicious content or phish users by redirecting them through a series of links. The ClamAV detection and ML classifier further support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9860

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://relleno-acidohialuronico.com/wp-content/plugins/super-forms/uploads/php/files/e70b194cab86bcac25c4f879a20f05dd/sidogaxozanomas.pdf In PDF document text
    • https://www.tonygssoulfood.com/wp-content/plugins/super-forms/uploads/php/files/466a92d9615b43480d4452e5033f85ff/pixifujulagizitereju.pdfIn PDF document text
    • http://allaboutdowney.com/userimages/97015988010.pdfIn PDF document text
    • https://brs.jo/userfiles/files/76811575963.pdfIn PDF document text
    • http://anhuicrew.com/upload_fck/file/2021-4-30/20210430234510611442.pdfIn PDF document text
    • http://gentlemensquartersbarbershop.com/wp-content/plugins/super-forms/uploads/php/files/9a2710e8ccd19aed4f24ee77ea51e9c9/juvekigeradarixofelimi.pdfIn PDF document text
    • https://tenshinorchids.com/FCKeditor_upload/file/tijoso.pdfIn PDF document text
    • http://mgmkt.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608e602f02016---lazojotajumo.pdfIn PDF document text
    • http://www.carolglassman.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080b9a082256---3814078394.pdfIn PDF document text
    • https://moraure.net/js/ckfinder/userfiles/files/robabozalizipapa.pdfIn PDF document text
    • https://noukos.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160a8f75e8f3d4---63574401752.pdfIn PDF document text
    • https://40parables.com/wp-content/plugins/super-forms/uploads/php/files/03e8d2ac6baf813cf2381623c3b96ba4/2835649849.pdfIn PDF document text
    • http://altaprecision.com/userfiles/file/dedazororigawibibufefume.pdfIn PDF document text
    • http://meble-tk.pl/userfiles/file/jafukubafisovoza.pdfIn PDF document text
    • http://www.tif.cn/wp-content/plugins/super-forms/uploads/php/files/mq1fe260dci317leomatj1dj9l/zapogarakifegumeniri.pdfIn PDF document text
    • http://jrpst.pl/userfiles/file/pupim.pdfIn PDF document text
    • http://midiabyz.com/wp-content/plugins/super-forms/uploads/php/files/d4828c93232e8da900cff660828c0780/98828283626.pdfIn PDF document text
    • https://braviengenharia.com.br/wp-content/plugins/super-forms/uploads/php/files/5hni1oksnv5lmkahlps2lfalui/93116565020.pdfIn PDF document text
    • http://miamiwars.pl/wp-content/plugins/super-forms/uploads/php/files/c5b1cf000f7cac0d8f89a624b00c6942/todelesodijavegivejazek.pdfIn PDF document text
    • https://agilitynd.com/wp-content/plugins/super-forms/uploads/php/files/a2b306368e66c91a22633bfc14eb3a9a/80581292267.pdfIn PDF document text
    • https://geneticapanama.com/userfiles/file/75546841277.pdfIn PDF document text
    • http://hzdsbg.com/uploadfile/1624847896.pdfIn PDF document text
    • https://fa-vietnam.com/webroot/img/files/lexigodurugejid.pdfIn PDF document text
    • http://lordbeaverbrook1973.com/clients/76835/File/65319415882.pdfIn PDF document text
    • http://securitydirect.it/wp-content/plugins/super-forms/uploads/php/files/bb9580080657ee1503f58cc9b65825fd/23562469010.pdfIn PDF document text
    • http://www.kidnuri.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077fd62d57d3---5682148450.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=reading+and+use+of+english+caePDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ec07.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC07 16628 bytes
SHA-256: 7509ce56aa6ec904b828c61191798dce31ee58c9a7ed480bd96c99d3e3a4437d
font_01_sfnt_off00011769.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11769 10704 bytes
SHA-256: 443534cb7f6ce49632409e17726a4ebbbc57f6e4afd37210d6d6fed32dfad8ea
font_02_sfnt_off00012fa7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12FA7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1