Malicious PDF — malware analysis report

Static analysis result for SHA-256 835c2aae934900ae…

MALICIOUS

PDF

85.3 KB Created: 2021-08-14 13:44:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 3426afb3514d25ce554cd0a35b897cb4 SHA-1: 684bf9171779710c8e7ac4ff3d0794a14fc650f6 SHA-256: 835c2aae934900ae70e1ec705f650a7011f1a0841863a22fe0a6cf7c105ab336
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external URIs and links to compromised WordPress uploads, indicating a link farm designed to redirect users to potentially malicious sites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://laborke.ru/uplcv?utm_term=financial+statements+analysis+book PDF link annotation
    • https://tonitomov.com/picture/file/86273067515.pdfIn PDF document text
    • http://vibrosystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160a1067b2ceb2---kowobiveseneta.pdfIn PDF document text
    • https://www.apartamentselsllacs.com/wp-content/plugins/super-forms/uploads/php/files/se1i0qasd1uuka26vuj5no3t4b/jasivebirepibabibom.pdfIn PDF document text
    • http://dogable.de/userfiles/file/rigubusabipidado.pdfIn PDF document text
    • https://agsposure.org/wp-content/plugins/super-forms/uploads/php/files/de02d2ba23b46f132ecfd1f6459392f0/32693866801.pdfIn PDF document text
    • http://premiumresourcing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609967f8b2a87---xapoluwo.pdfIn PDF document text
    • http://adanateknikservis.web.tr/wp-content/plugins/formcraft/file-upload/server/content/files/161091f9990971---40859463480.pdfIn PDF document text
    • https://prana.video/wp-content/plugins/super-forms/uploads/php/files/98be421kfh7re6or1urcldhl49/78455637755.pdfIn PDF document text
    • https://faktxeber.ru/resimler/files/guvibijeferisapapizubo.pdfIn PDF document text
    • http://lafayetteconnections.com/clients/52818/File/jijapopug.pdfIn PDF document text
    • http://famillespourstarlight.org/clients/a/a9/a9b42c05011d3bb27e7f7ec2ed30324f/File/9451774528.pdfIn PDF document text
    • https://shining4u.com/wp-content/plugins/super-forms/uploads/php/files/e9e85352cd97e096e0951f164258bf5b/66640640627.pdfIn PDF document text
    • http://www.siscard.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a52d3db4651---vivizagujepidoxegewuweviv.pdfIn PDF document text
    • https://prikolnaya.com/wp-content/plugins/super-forms/uploads/php/files/287d4e933986fe51302d1e2f00410d64/xefufovetofevijavig.pdfIn PDF document text
    • http://luchetti.it/userfiles/files/79708230206.pdfIn PDF document text
    • http://entiambalaj.com/upload/file/xamuk.pdfIn PDF document text
    • http://minhledtran.com/luutru/files/98834361480.pdfIn PDF document text
    • http://petrduchek.com/files/29189372686.pdfIn PDF document text
    • https://psfund.org/public/uploads/files/cms_files/88560507036.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_off0000eb3d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB3D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001034f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1034F 16668 bytes
SHA-256: 09769ba21aeb874b30a0e13e42414d64286ea7d71ab71a95e797a4aa1e51c741
font_02_sfnt_off00012ec8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12EC8 10616 bytes
SHA-256: a1e83dce7a52615f7a7e1cfd6d726613d9c8f13a29b9d9ebb13fc83897c03eec