Malicious PDF — malware analysis report

Static analysis result for SHA-256 66d40ed028637e7c…

MALICIOUS

PDF

79.6 KB Created: 2021-09-17 04:50:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 497671ebaa35d47cd9b81dfe314588a7 SHA-1: 1137152b0b4bcb7248d4e05f93d2c56ec2f9fd8a SHA-256: 66d40ed028637e7c0a057a22356718a7f4b076dbce2ed13deb4e3dd0b1aa7512
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded links to external websites, many of which are algorithmically generated and hosted on disposable domains, indicating a phishing or malware distribution attempt. The ClamAV detection and ML classifier strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and link farm behavior are consistent with techniques used to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://oniceh.ru/uplcv?utm_term=make+mp4+to+mp3 PDF link annotation
    • http://stitesattorney.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/valovurapopajiworise.pdfIn PDF document text
    • http://poptheme.cn/uploadfile/files/20210910_180046.pdfIn PDF document text
    • http://fueandhair.com/userfiles/files/20946514001.pdfIn PDF document text
    • https://newat.ru/wp-content/plugins/super-forms/uploads/php/files/b3b0a883225a85061a44caa350588510/latifaxo.pdfIn PDF document text
    • http://timatey.kz/wp-content/plugins/super-forms/uploads/php/files/o3hvfhealr1hgvocfjfj6gl4k6/pitegarado.pdfIn PDF document text
    • http://wordtmann.beckbauer.eu/ckfinder/userfiles/files/2089207048.pdfIn PDF document text
    • http://ambulatorioveterinariovianello.eu/userfiles/files/vepemopigeladasuvevira.pdfIn PDF document text
    • http://sanitaerprofi.ch/fckeditor/editor/images/file/duwekapoxamusisozupozura.pdfIn PDF document text
    • http://muasamhangmy.com/ckfinder/userfiles/files/78305632751.pdfIn PDF document text
    • http://take114.kr/FileData/ckfinder/files/20210917_655E563D26044D98.pdfIn PDF document text
    • http://markone-tools.com/upload/files/17210441125.pdfIn PDF document text
    • http://xn--12cfu9bc1efac9a9azfdsb7b9d1f0j.net/ckfinder/userfiles/files/74850315285.pdfIn PDF document text
    • http://odontoflash.eu/userfiles/files/fufedejavixiji.pdfIn PDF document text
    • http://rainternacional.com/userfiles/file/xeniza.pdfIn PDF document text
    • https://5uempat.com/contents/files/81230438902.pdfIn PDF document text
    • http://paolacaone.eu/userfiles/files/zeviwusavenijuvaw.pdfIn PDF document text
    • http://pro-roubenky.cz/UserFiles/File/30543217974.pdfIn PDF document text
    • https://gastriklandsbf.se/UserFiles/files/48112341126.pdfIn PDF document text
    • http://purofirstli.net/userfiles/file/67906459192.pdfIn PDF document text
    • https://hetodon.com/fckeditorfiles/file/72062337067.pdfIn PDF document text
    • http://karpatskiles.ru/store/files/febir.pdfIn PDF document text
    • https://perfecthospital.net/ckfinder/userfiles/files/93506793388.pdfIn PDF document text
    • http://bbpcosmetics.com/admin/upFiles/2021-9/file/xobafatenapoli.pdfIn PDF document text
    • https://insinkerator.us/images/uploaded/file/mujuxupojapozoxelajo.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_off0000d449.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD449 17764 bytes
SHA-256: 9b2e5b6ff834ad80da7552ebd11efe0167ea3b3b83e6923d0eb25d1d0ca51907
font_01_sfnt_off000101fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101FD 10240 bytes
SHA-256: 0c3245f084ad37b5b1091c2b5425f393981c7fdd777ceeb43fc320286c5cbbe5
font_02_sfnt_off00011918.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11918 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1