Malicious PDF — malware analysis report

Static analysis result for SHA-256 a0038ffddd6c2185…

MALICIOUS

PDF

81.5 KB Created: 2021-10-12 22:06:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-22
MD5: ab461b4e2cc7c17b1846accbeebc69db SHA-1: fd64103c9a4d91b21fc3d4b4adbd74108a52da1c SHA-256: a0038ffddd6c2185139424191d456c5d28f9df86eef8e21f70ff387dffa99a40
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous embedded URLs pointing to other PDF files, likely to obscure the final malicious destination. The presence of a 'Password-protected archive handoff' heuristic suggests a multi-stage attack where the user is prompted to open a password-protected archive, which is a common tactic to bypass security scanning.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • 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://kojeneckezbozi.eu/userfiles/file/goloziwozewilugikawo.pdf In PDF document text
    • https://www.babetravelling.com/ckfinder/userfiles2/files/87289548968.pdfIn PDF document text
    • https://regenerativetherapyforpain.com/wp-content/plugins/super-forms/uploads/php/files/4ef04fc9029979e449eedb017aa5bd0f/vusepinujafovawom.pdfIn PDF document text
    • https://www.bosingels.nl/ckfinder/userfiles/files/guxivam.pdfIn PDF document text
    • https://avflash.nl/upload/files/zezavaduvufoza.pdfIn PDF document text
    • http://rambud.pl/uploaded/file/94353008973.pdfIn PDF document text
    • http://a-b-i-s.net/layout/bilder/file/lixumironafu.pdfIn PDF document text
    • http://garant-fond.ru/ckeditor/ckfinder/userfiles/Images/files/durizokujamogagig.pdfIn PDF document text
    • http://elma1.ru/!upload/files/40423735459.pdfIn PDF document text
    • https://pt-olympus.com/contents/files/14562505516.pdfIn PDF document text
    • https://moderator.lt/components/com_mijoshop/opencart/image/data/files/51072771099.pdfIn PDF document text
    • https://trungtamgiasuhcmmq.com/uplaod/quangtri/files/tiparitojolad.pdfIn PDF document text
    • https://butterfly-propertymanagement.com/userfiles/file/lazefotidumifi.pdfIn PDF document text
    • http://edu-family72.ru/content/images/uploads/file/43651153404.pdfIn PDF document text
    • https://nisahanpin.com/calisma2/files/uploads/92382677809.pdfIn PDF document text
    • http://legalinet.eu/userfiles/files/86109681471.pdfIn PDF document text
    • http://realestatespoznan.com/uploads/xarexi.pdfIn PDF document text
    • http://broadgatecapital.com/userfiles/file/78783448827.pdfIn PDF document text
    • https://greenbins.ca/ckfinder/userfiles/files/wimesepovunavolikixi.pdfIn PDF document text
    • http://architettobotteonpierpaolostudioabacus.it/userfiles/files/xavukoperetajizukabezegaf.pdfIn PDF document text
    • https://qkon.ca/images/file/nizobitoxedaxajogesebu.pdfIn PDF document text
    • https://www.crossfitparamaribo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16163d91e5c898---vukuzelavukosufesusemugo.pdfIn PDF document text
    • https://griby.biz/ckfinder/userfiles/files/vekafomida.pdfIn PDF document text
    • http://feedproxy.google.com/~r/MbOu/~3/cmwvf4RlXg4/uplcv?utm_term=how+to+find+the+solution+to+a+systemPDF 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_off0000d618.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD618 19376 bytes
SHA-256: 9d11a3d83d4480582d75b5beffe34c9cab4a27f3cbbd5eca757c00e869ed792d
font_01_sfnt_off000107d9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107D9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011ff0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FF0 10812 bytes
SHA-256: a503619ea2925e3d4c263bf0229e079ddda0aeb5e364337ee7bc2bd708effc91