Malicious PDF — malware analysis report

Static analysis result for SHA-256 e61adc35ca29ea94…

MALICIOUS

PDF

77.0 KB Created: 2021-09-23 01:31:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: c4203f58a733bc162fd6342f2806ae7f SHA-1: d1b93b31a51f5570d29ef7fb68ddcf163845f245 SHA-256: e61adc35ca29ea94293a49fb28a2fb28f965b91923298e34c128b85ec2b42afe
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external PDF files hosted on potentially disposable domains, indicating a link farm or redirection scheme. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware distribution. Although no scripts were explicitly extracted, the presence of external links and the heuristic 'PDF_RANDOM_URL_LINK' suggest an attempt to redirect the user to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://xprchemical.com/upload/files/fidusar.pdf In PDF document text
    • http://www.civilhospitalpalampur.in/img/uploads/files/faxosotore.pdfIn PDF document text
    • http://bangdinhphucat.com/quangbasanpham/app/webroot/upload/image/files/65367314048.pdfIn PDF document text
    • http://mjengo.org/FCKeditor/editor/filemanager/connectors/php/connector.php?Command=FileUpload&Type=File&CurrentFolder=%2Ffile/pirujosog.pdfIn PDF document text
    • http://tidomusica.com/uploads/files/202109031621129964.pdfIn PDF document text
    • http://shipagents.nl/uploadfiles/file/dugebojuxofutafugepe.pdfIn PDF document text
    • http://jpiano.net/userData/ebizro_board/file/45376402664.pdfIn PDF document text
    • http://valencia.thepokeluau.com/uploads/files/26507592708.pdfIn PDF document text
    • https://kingcarmotorista.net/uploads/files/rokukuleraxajiden.pdfIn PDF document text
    • https://ccaquebec.com/userupload/files/binatolevozuselutadusil.pdfIn PDF document text
    • http://www.portaldasfreguesias.com/portugal/vianadocastelo/vianadocastelo/geraz_do_lima_sta_maria/ckeditor/ckfinder/file/mepawudefuneto.pdfIn PDF document text
    • http://evaemlak.com/userfiles/file///12642304637.pdfIn PDF document text
    • https://zaragozadenoche.es/upload/files/vajebo.pdfIn PDF document text
    • https://varida-tech.com/ckfinder/userfiles/files/10149297230.pdfIn PDF document text
    • http://daiduongmetal.com/uploads/ckfinder/files/wiwivezetojaw.pdfIn PDF document text
    • http://studiomuraca.eu/userfiles/files/sulelasatube.pdfIn PDF document text
    • http://sushiloverca.com/uploads/files/56266825309.pdfIn PDF document text
    • http://ambulatorioveterinarioilghirlandaio.it/userfiles/files/20000226193.pdfIn PDF document text
    • http://whipitleather.com/userfiles/file/96317613051.pdfIn PDF document text
    • https://kaemsp.org/upload/editor/file/zipisurowe.pdfIn PDF document text
    • http://www.next-conseil.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1613faa6e27258---4365951569.pdfIn PDF document text
    • https://okinawa4d.com/contents/files/wozamuzog.pdfIn PDF document text
    • http://msslink.ru/userfiles/files/juritofuvonos.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=pixel+4+wallpaper+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_off0000caa4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCAA4 10112 bytes
SHA-256: c9d3ac62edea6ac3ebc012ffe644297c1776dbac448e90c1c7952c09b5ce8099
font_01_sfnt_off0000e16c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE16C 17420 bytes
SHA-256: febcc210d65800be5c9d56b4e988e27bd8223dca3e1eb9711c60b0b08eb41261
font_02_sfnt_off00010ee0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10EE0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1