Malicious PDF — malware analysis report

Static analysis result for SHA-256 b13ac7f7a33f5016…

MALICIOUS

PDF

69.9 KB Created: 2021-09-26 12:49:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 3a6f7784aaaa0c1d60e61fc91982fce5 SHA-1: f578f0b8951cd7c7888f8ba3cafef7848569437b SHA-256: b13ac7f7a33f501626416bb3433553d3444269c656d948c234e47057a49032be
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many of which are hosted on compromised or disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery. The presence of external URIs and compromised CMS upload links points towards an attempt to exploit user trust by directing them to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://medvor.ru/uplcv?utm_term=sausage+party+123movies PDF link annotation
    • http://mayjack.com/upload/files/tumadifokuwe.pdfIn PDF document text
    • https://justforjetscatering.com/userfiles/image/files/tupezopiguxuwosuwe.pdfIn PDF document text
    • http://nataliashishkina.com/userfiles/file/10142903216.pdfIn PDF document text
    • https://igraonica.me/userfiles/file/rawixakevogasawivaz.pdfIn PDF document text
    • http://abwnickersonplaza.com/uploads/files/13103515212.pdfIn PDF document text
    • http://quick-thailand.com/images/uploads/file/9000117731.pdfIn PDF document text
    • http://prtourusa.com/FileData/ckfinder/files/20210920_1CFE917075B34310.pdfIn PDF document text
    • https://bestrecycledautoparts.net/images_i/file/90600453467.pdfIn PDF document text
    • https://ddriu.hu/wp-content/plugins/super-forms/uploads/php/files/b4901232d7caad5beb5103b86261c306/9888824203.pdfIn PDF document text
    • http://jjw-led.com/userfiles/file/kazez.pdfIn PDF document text
    • http://4rrecycle.com/files/file/76025367844.pdfIn PDF document text
    • https://centar-znr-zop.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1614f6f7cab475---97455676729.pdfIn PDF document text
    • https://linhngapt.vn/upload/files/38825918219.pdfIn PDF document text
    • http://kdbelektrotechniek.nl/uploads/file/bijavifeza.pdfIn PDF document text
    • http://krajinar.cz/soubory/files/36974211786.pdfIn PDF document text
    • http://lecieldesandes.fr/ckfinder/userfiles/files/82874111808.pdfIn PDF document text
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614273fb8a978---81021248390.pdfIn PDF document text
    • https://k85shj16h-561lt.com/contents/files/dusosomoxorokavolevurudi.pdfIn PDF document text
    • https://oreopay57.com/ckfinder/userfiles/files/wajoxunevexusoketat.pdfIn PDF document text
    • https://wronba.pl/uploads/wysiwyg/file/80454373250.pdfIn PDF document text
    • http://terralis.eu/catalogue_dynamique/file/xoleneroxidebopenagizuxow.pdfIn PDF document text
    • http://birizgardenhotel.com/userfiles/file/53106327483.pdfIn PDF document text
    • https://www.grecosalesinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/16148eaa4c9b20---xetefawinum.pdfIn PDF document text
    • 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_off0000b0be.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB0BE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c8d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC8D5 11144 bytes
SHA-256: e833c6be59bd4ad1f3bbef252e469ba168d10fb46dfb45706b2c24f680bfd002
font_02_sfnt_off0000e30a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE30A 14852 bytes
SHA-256: e5903c0c947e272303caf9cce64342cc2e3b9ba60c6969a55c96d64b7eb6bff4