Malicious PDF — malware analysis report

Static analysis result for SHA-256 43da92a94ee02496…

MALICIOUS

PDF

73.4 KB Created: 2021-09-20 16:42:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 74801655a00c200cf53984b2c2a165aa SHA-1: 454e2e91e8f5c204ed338032c8d474863c8566a4 SHA-256: 43da92a94ee024967b5fd7d43659fcb421c9675aadcfba6c4ad65b42378dd6d5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, indicating a high likelihood of malicious intent. Heuristics identified the document as a link farm, with numerous URLs pointing to potentially compromised websites or disposable hosting, suggesting a phishing or malware distribution scheme. The presence of external URIs and link farms strongly supports the attack pattern of luring users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://drafthe.ru/uplcv?utm_term=android+os+virtualbox PDF link annotation
    • https://duragloss.pl/userfiles/file/vuvapekujelukuw.pdfIn PDF document text
    • https://noks.cz/wp-content/plugins/formcraft/file-upload/server/content/files/1612f076540b0c---tagab.pdfIn PDF document text
    • http://changwontour.kr/FileData/ckfinder/files/20210920_8482B80B5EC36003.pdfIn PDF document text
    • https://myparrotfood.com/user_files/files/69433565617.pdfIn PDF document text
    • https://vallejardin.com/wp-content/plugins/super-forms/uploads/php/files/c4a33da41bbe6707d78a3825b6194c61/23346359572.pdfIn PDF document text
    • http://veitali.com/upload/files/24177846844.pdfIn PDF document text
    • http://serramentisiciliano.it/userfiles/files/kenazovakiwumagedofujaw.pdfIn PDF document text
    • https://nutricount.cz/UserFiles/File/58739938893.pdfIn PDF document text
    • https://karlholmbygg.se/UserFiles/files/69550357237.pdfIn PDF document text
    • http://thefutureofgolf.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16132f9e16e14a---lalokaranesudo.pdfIn PDF document text
    • https://mcq.bmtinhoc.vn/InteriorWeb/images/images_news/files/8911962200.pdfIn PDF document text
    • http://webinaris.net/ckfinder/userfiles/publics/files/48445982902.pdfIn PDF document text
    • https://lisacutler.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e06dbcecc2---21318864253.pdfIn PDF document text
    • https://podgoricki-klub.me/userfiles/file/vawot.pdfIn PDF document text
    • http://musthighschool.mn/ckfinder/userfiles/files/96778702742.pdfIn PDF document text
    • http://lyzjkgm.com/d/files/60727729140.pdfIn PDF document text
    • http://liveisagenix.com/ckfinder/userfiles/files/97334442836.pdfIn PDF document text
    • http://sluchatka-shop.cz/files/upload/files/89750022629.pdfIn PDF document text
    • http://cjmfgx.morefriendship.com/upload/files/jabupoxeba.pdfIn PDF document text
    • https://prawobrzeze.info/userfiles/file/dufujojam.pdfIn PDF document text
    • http://botosani.ro/img/uploads/file/89479106729.pdfIn PDF document text
    • http://sanfrancescovet.com/userfiles/files/muguruvixapuj.pdfIn PDF document text
    • http://bright-mineral.com/uploadfile/file/2021091019324934.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_off0000bbc0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBBC0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d3d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD3D2 17056 bytes
SHA-256: 605bfe4e8094c5510676cedda3a4597693c63e50998cb3d944844cae73466083
font_02_sfnt_off00010027.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10027 10500 bytes
SHA-256: 6b277ae6f76115d2eeed7cda9b95eae28790b23c48023d7ee46326ab032121a9