Malicious PDF — malware analysis report

Static analysis result for SHA-256 ba221dd709e2943a…

MALICIOUS

PDF

74.3 KB Created: 2021-09-19 12:51:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 6d0cbf7c8a6217d1de8d8a9ea8ce639a SHA-1: 7b65db76cf0bbd2294681f23dde59007b9e31794 SHA-256: ba221dd709e2943aaa1d58386d18e9c8d73a9b5f4bc4be2fe18bbf46ebd142fe
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised or disposable hosting domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery through these links. No scripts were extracted, and the document body was unreadable, so the attack pattern is inferred from the URL analysis and heuristic firings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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 http://sb-78.ru/files/file/tozipilowezegawe.pdf In PDF document text
    • https://ecpa.fr/uploaded/file/26819476122.pdfIn PDF document text
    • http://vibrosystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/161320681bd213---63859919138.pdfIn PDF document text
    • http://clingac.es/d/files/42757736413.pdfIn PDF document text
    • http://veterinariacomportamentale.it/userfiles/files/libagurivojubexezasidosu.pdfIn PDF document text
    • http://hum-lucknow.org/test/fckeditor/file/44733726029.pdfIn PDF document text
    • http://rpsbchamber.org/editorData/file/69472052321.pdfIn PDF document text
    • http://luckysim.com/userfiles/file/47870193802.pdfIn PDF document text
    • http://nickelsgrafikdesign.de/ckfinder/userfiles/files/giwisufetuxum.pdfIn PDF document text
    • http://www.singchai.co.th/ckfinder/userfiles/files/80794685642.pdfIn PDF document text
    • http://mnarch.it/userfiles/files/xagevawitowimun.pdfIn PDF document text
    • http://ceramvetro.net/userfiles/file/puxoxevi.pdfIn PDF document text
    • https://trickapotisk.cz/webpagebuilder/ckfinder/userfiles/files/vosuzexatobasit.pdfIn PDF document text
    • http://acmemask.com/upfiles/editor/files/jizomopikaxagiwe.pdfIn PDF document text
    • http://www.scea.edu.mn/ckfinder/userfiles/files/negak.pdfIn PDF document text
    • https://paloaltospeakerseries.com/wp-content/plugins/super-forms/uploads/php/files/7ea5ec887cf4a794a0f38c96beee4f15/sizutivi.pdfIn PDF document text
    • http://mynigaoe.com/upload/file/20210910054158.pdfIn PDF document text
    • http://www.enredmail.com/templates/files/idCliente_/file/dobebawolaziwevimonet.pdfIn PDF document text
    • http://riasztoszolnok.hu/admin/fck_upload/file/39110248731.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134a7fee0845---12510640979.pdfIn PDF document text
    • https://nexusmediation.nl/files/30708586482.pdfIn PDF document text
    • http://www.instalacionescueto.com/nueva/ckfinder/userfiles/files/63948986575.pdfIn PDF document text
    • http://tienphat.vn/imagesflashupload/file/tuzepatulumezu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=how+to+remove+imo+adsPDF 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_off0000c0c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC0C6 16820 bytes
SHA-256: 134afe711f777678123c64f43493ceec41c4e7a4d0c3204b9185d2490ff8cd97
font_01_sfnt_off0000ebf9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBF9 10404 bytes
SHA-256: b83f6061fc5ac9068453be4048aa1bcb3b08bbd0390dc07dae7cbe2de7c12aba
font_02_sfnt_off00010397.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10397 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1