Malicious PDF — malware analysis report

Static analysis result for SHA-256 98f309f62c5d85df…

MALICIOUS

PDF

74.8 KB Created: 2021-09-19 02:49:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: b8e36abf03b572e7846f90151929cede SHA-1: e4bef57baa1e7a983faaf89ae65f9ab96c512bae SHA-256: 98f309f62c5d85df363dd4ef441068e959099d57ed7adce95557f733a4f41546
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, with one directly pointing to an IP address, indicating a link farm designed to redirect users to potentially malicious content. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' strongly suggests this is a tactic for phishing or malware distribution. While no scripts were explicitly extracted, the nature of the embedded URIs and the ML classification point towards malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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
  • Clickable URI points to raw IP address medium PDF_URI_IP_LITERAL
    PDF contains a clickable HTTP(S) action whose host is a literal IPv4 address. Legitimate documents normally link to named domains; raw-IP destinations are common in disposable phishing and malware-delivery infrastructure.
  • 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 http://nhasachnguyenvancu.com/Images_upload/files/59896660320.pdf In PDF document text
    • http://forma8.kz/ckfinder/userfiles/files/92577508402.pdfIn PDF document text
    • http://nawooelcs.com/upload/userfiles/2021/09/files/210915200109.pdfIn PDF document text
    • http://www.motocams.cz/ckfinder/userfiles/files/xinevas.pdfIn PDF document text
    • http://bm-shower.com/userfiles/files/9056425137.pdfIn PDF document text
    • https://marksiegeldds.com/wp-content/plugins/super-forms/uploads/php/files/1d2cedd983d3b8e6b7ab8291c22e7f9d/31070414251.pdfIn PDF document text
    • https://istanajp.net/contents/files/80536926774.pdfIn PDF document text
    • http://185.33.116.142/~bbyacht01/upload/files/39207219618.pdfPDF link annotation
    • http://www.biogreeno.com/cms/ckfinder/userfiles/files/42722804315.pdfIn PDF document text
    • https://trungtammatnamviet.vn/upload/files/diwafarafudilav.pdfIn PDF document text
    • https://slicktechproducts.com/newerac2c/userfiles/file/waxerudowafofixunuxoxurez.pdfIn PDF document text
    • https://verredistri.fr/xmedia/file/61719783290.pdfIn PDF document text
    • https://tvmreza.tv/ckfinder/userfiles/files/ferumifoz.pdfIn PDF document text
    • http://bobas24.pl/Upload/file/80647480422.pdfIn PDF document text
    • https://ooobelkom.ru/ckfinder/userfiles/files/dumoruwazud.pdfIn PDF document text
    • https://rumahbaruku.com/contents/files/12619726261.pdfIn PDF document text
    • http://cpgny.com/userfiles/files/6647176125.pdfIn PDF document text
    • http://vector-luczak.pl/new/fck_user_files/file/nonatawunapajatinujudige.pdfIn PDF document text
    • http://brenna-ski.pl/userfiles/file/ligazewizofaju.pdfIn PDF document text
    • http://notar-frings.de/userfiles/file/wiwakiv.pdfIn PDF document text
    • http://ruresept.ru/files/file/37618591841.pdfIn PDF document text
    • http://novo-foto.ru/ckfinder/userfiles/files/97556809303.pdfIn PDF document text
    • http://mp-hd.de/data/aktualnosci_imgs/file/pavovem.pdfIn PDF document text
    • https://apartmani-mestrovic-krk.hr/files/voxezuvatakarevolat.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=monkey+king+apkPDF 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_off0000bde2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBDE2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d5f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5F4 18892 bytes
SHA-256: 9fcf21160915dca6807f2c8890ad9628d1e10d7788b4d7ac899dcfb2b1d1dce1
font_02_sfnt_off00010706.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10706 10216 bytes
SHA-256: 7c3f327c3dcc7e80bd4b283e2e11ddc33667fb288d8553bbde9f9f3fbcfa81ae