Malicious PDF — malware analysis report

Static analysis result for SHA-256 bf84340ec2285f0a…

MALICIOUS

PDF

82.9 KB Created: 2021-09-18 03:04:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 75db94a9ad69cc8585e192d804d00a45 SHA-1: a8866a382adfd27f9a6aab05a6ad68f506260afc SHA-256: bf84340ec2285f0a25505e7b4f0ba09c7d6c671b4a9ba3d5b8aac0cdb691f4fc
142 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript and a large number of external URLs, many of which appear to be part of a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. The embedded JavaScript suggests an attempt to execute code or redirect the user, potentially to download a second-stage payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://coretry.ru/uplcv?utm_term=remove+clothes+from+photo+apk+download PDF link annotation
    • http://konemara.hu/userfiles/file/38886380217.pdfIn PDF document text
    • https://pemaboutiquehotel.com/assets/userfiles/files/68370340710.pdfIn PDF document text
    • http://zabradli-znerezu.cz/userfiles/file/71842932247.pdfIn PDF document text
    • http://ccswcd.com/userfiles/file/5340325642.pdfIn PDF document text
    • http://bernardthevenet.fr/ckfinder/userfiles/files/75590732677.pdfIn PDF document text
    • http://ombs.ru/uploads/files/78478539300.pdfIn PDF document text
    • https://imaggu.com/ci/userfiles/files/65747148146.pdfIn PDF document text
    • http://komputerzagrosze.pl/userfiles/file/85095708665.pdfIn PDF document text
    • https://kcharp.com/ckfinder/userfiles/files/38157605056.pdfIn PDF document text
    • http://www.ecvbrass.ch/user/web/file/78623609488.pdfIn PDF document text
    • http://carbontuning.ru/file/43235396384.pdfIn PDF document text
    • https://polinagerz.ru/wp-content/plugins/super-forms/uploads/php/files/l8v7qll92ucrk9iqm5vl22ksuj/41639203210.pdfIn PDF document text
    • https://corpeverest.com/ckfinder/userfiles/files/fenilisofapil.pdfIn PDF document text
    • https://www.pollackmihalyiskola.hu/ckfinder/userfiles/files/fisakok.pdfIn PDF document text
    • https://astoriareiki.com/wp-content/plugins/super-forms/uploads/php/files/39e9a37230ffebc6f4754272e6f8a12c/64326379885.pdfIn PDF document text
    • https://sieuthigo.vn/upload/ck/files/nuripomalidelotevafo.pdfIn PDF document text
    • https://giaynangchieucao.com/userfiles/file/35638471244.pdfIn PDF document text
    • https://sunriseinnjasper.com/nbloom/fckuploads/file/viluxegizunolomejebavogu.pdfIn PDF document text
    • http://fedime.org/imagenes/23641688582.pdfIn PDF document text
    • http://exdebt.bg/userfiles/file/wutalagimufudoj.pdfIn PDF document text
    • https://chasehr.in/userfiles/file/vidopuzelujaxovuvowawu.pdfIn PDF document text
    • http://mlsconsulting.net/cms/files/File/wavukixemudafinilela.pdfIn PDF document text
    • http://algarestofos.pnh.pt/js/ckfinder/userfiles/files/dirip.pdfIn PDF document text
    • http://bestorkate.com/uploads/ckeditor/files/waxamefi.pdfIn PDF document text
    • https://vaynhanh365.net/contents/files/71496704925.pdfIn PDF document text
    • http://laboratoriologos.it/userfiles/files/wirasufa.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_off0000df04.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF04 11084 bytes
SHA-256: 9c93f7552076028c651c6731300e3021a9c1c4dbd3ef8bcf695c67dc502117e6
font_01_sfnt_off0000f8ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8CA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000110dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110DC 17540 bytes
SHA-256: 0cfa5ae46a472beb0abdc2800c6bdd0b610d0481679a827a6d7fefb80168f057