Malicious PDF — malware analysis report

Static analysis result for SHA-256 c9b53f4d6758eb9a…

MALICIOUS

PDF

75.9 KB Created: 2021-09-09 21:15:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: d105fe22a551ab798aa017c580320ed5 SHA-1: 0c3fbfeda7291314813860141ed43a355edaa74c SHA-256: c9b53f4d6758eb9ab870b9a3425e0058c40ba5efe0ad6172f552e40aa6eea0cd
174 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm and presents a deceptive download button. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://braindevelopmentmaps.org/userfiles/files/mirulukonoposepakaweta.pdf In PDF document text
    • http://fgosvo.ru/files/files/wigozopufifamak.pdfIn PDF document text
    • https://thefertilizerequipment.com/d/files/wimob.pdfIn PDF document text
    • https://samngaimarble.com/html_upload/file/55268275715.pdfIn PDF document text
    • http://studioesflores.pl/obrazy/file/zazuwadajixozesapemob.pdfIn PDF document text
    • http://veronicanealhome.com/wp-content/plugins/formcraft/file-upload/server/content/files/2/16135d28ca33a0---24267886178.pdfIn PDF document text
    • http://www.fullmooneye.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139218027f3e---63631517763.pdfIn PDF document text
    • http://art-ball.net/files/file/bazamumeba.pdfIn PDF document text
    • http://shriadinathbank.com/uploads/49897806617.pdfIn PDF document text
    • http://recviem.ru/img/upload/sexiwaxobobawiwolukewi.pdfIn PDF document text
    • http://japanbizkorea.com/userData/ebizro_board/file/vevegivexuk.pdfIn PDF document text
    • http://lucchetta.net/userfiles/files/27932310839.pdfIn PDF document text
    • http://ambulatorioveterinarioilghirlandaio.it/userfiles/files/34379337355.pdfIn PDF document text
    • https://radiosmile.hu/upload/file/65818830093.pdfIn PDF document text
    • http://lncxjzxxw.com/upload_fck/file/2021-9-5/20210905171458279818.pdfIn PDF document text
    • https://sanaspinler.net/calisma2/files/uploads/neguxesow.pdfIn PDF document text
    • http://crystal-lamp.ru/uploads/files/4901960954.pdfIn PDF document text
    • http://hataylezzeti.com/resimler/files/64316775533.pdfIn PDF document text
    • http://pusheng168.com/uploadfiles/20210908061928.pdfIn PDF document text
    • http://twfindia.in/userfiles/files/74969878502.pdfIn PDF document text
    • https://cvsc.co/userfiles/file/wulepotobu.pdfIn PDF document text
    • http://nyett.hk/uploads/news/files/77619291939.pdfIn PDF document text
    • https://klubkanine.com/home/klub/public_html/ckfinder/userfiles/files/fogipejidenezapopixo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=gta+vc+android+cheatsPDF 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_off0000c49f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC49F 17544 bytes
SHA-256: 98c51f9aa0242b2fbf13963c610167ab175cd36477fa3f03aa29f9eb59e2d3ef
font_01_sfnt_off0000f238.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF238 10524 bytes
SHA-256: 987b76158649898c74a4ad2be5efdf90997d193753e35103b4532528be62952c
font_02_sfnt_off00010a31.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A31 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1