Malicious PDF — malware analysis report

Static analysis result for SHA-256 35a9e8b28fbc860b…

MALICIOUS

PDF

70.2 KB Created: 2021-09-18 15:18:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 8e87c3929259a87a0c5f66ba1a0d312a SHA-1: a0db39a34c312bef267db89da17b3af6372373b0 SHA-256: 35a9e8b28fbc860bfeba2c29bcc1561b0d2e508eb74ed96220d05b70f8a1fee9
166 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, exhibiting characteristics of a phishing or malware distribution campaign. The PDF contains a high number of external links, many of which are algorithmically generated and hosted on disposable domains, indicating a link farm or redirection scheme. The presence of PDF_RANDOM_URL_LINK and PDF_SEO_DISPOSABLE_LINK_FARM heuristics strongly suggests malicious intent to distribute further payloads or lead users to phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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 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 https://garglob.ru/uplcv?utm_term=cadillacs+and+dinosaurs+free+download+for+android PDF link annotation
    • http://precedent.by/_newsite/images_from_html_editor/file/27335728774.pdfIn PDF document text
    • https://primax.fr/wp-content/plugins/super-forms/uploads/php/files/9fo3b8opn51cr6pn2snb520ri3/liwamibesizoput.pdfIn PDF document text
    • http://ambulatorioveterinarioscapindandrea.it/userfiles/files/47213745659.pdfIn PDF document text
    • http://digifast.cz/userfiles/kelopitovezasan.pdfIn PDF document text
    • http://maysoi.com/hinhanh_fckeditor/file/zajonetivof.pdfIn PDF document text
    • https://baruipur.org/ckfinder/userfiles/files/81103176722.pdfIn PDF document text
    • https://bitree.com/ckfinder/userfiles/files/41693202331.pdfIn PDF document text
    • https://pcparts.fr/ckfinder/userfiles/files/gonidoro.pdfIn PDF document text
    • http://bjyhyy.cn/filespath/files/20210908082454.pdfIn PDF document text
    • http://residencecarlofelice.com/userfiles/files/nobowafono.pdfIn PDF document text
    • http://schule.havonix.com/ckfinder/userfiles/files/41774934372.pdfIn PDF document text
    • http://www.mbk-montage.nl/ckfinder/userfiles/files/45338770762.pdfIn PDF document text
    • http://vilocom.net/webroot/img/files/30309936920.pdfIn PDF document text
    • http://agroanaliz.by/upload/editor/files/69745809470.pdfIn PDF document text
    • http://www.barankayalar.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/161402cea7b3a6---wekupiwagikoki.pdfIn PDF document text
    • https://ita.kru.ac.th/ckfinder/userfiles/files/xezasodijetulaxurokupubex.pdfIn PDF document text
    • https://naveenent.com/administrator/imagetemp/file/74942088418.pdfIn PDF document text
    • https://tbsva.org/Upload/files/20210905153258.pdfIn PDF document text
    • https://karinbentum.nl/uploads/file/bixabal.pdfIn PDF document text
    • https://506hlapeta.com/files/file/97218682158.pdfIn PDF document text
    • http://files.ibiza-ferien.de/file/xobafobaf.pdfIn PDF document text
    • http://rtm-plus.ru/ckfinder/userfiles/files/52760339631.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_off0000b38e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB38E 15248 bytes
SHA-256: b9902f5b8b1bde79913f41ae02cd556fb6a8b21f299114280ffb359ef762814e
font_01_sfnt_off0000da6d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA6D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f284.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF284 10588 bytes
SHA-256: 08a0043502488d7598aec76c36003ce99afb2e2056993c8e29a675e9673419d0