Malicious PDF — malware analysis report

Static analysis result for SHA-256 1fee742fc83e7650…

MALICIOUS

PDF

72.0 KB Created: 2021-09-10 22:52:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 725405cb39aa77bc98bacbf9412e7b3f SHA-1: e123d5913cd5a06afc327f62803595fab6863657 SHA-256: 1fee742fc83e7650d81e5afd85c88d3db8919d0b69f1bce310709b01b84ffe0e
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file identified as malicious by ClamAV and an ML classifier. It contains numerous embedded URLs, many of which point to disposable domains and are structured as a link farm, indicating a potential phishing or malware distribution scheme. The heuristic 'PDF_RANDOM_URL_LINK' specifically flags a link to an algorithmically generated URL, further supporting this assessment. No scripts were extracted, but the structure and URL patterns strongly suggest an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://conniecorsentino.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/84204796790.pdf In PDF document text
    • https://olterus.com/contents/files/zuvijez.pdfIn PDF document text
    • http://rockbond-aac.com/id-admin/fckImages/file/tizenusajevupe.pdfIn PDF document text
    • http://gsemilia.it/userfiles/files/9441696810.pdfIn PDF document text
    • http://pizzeria-millemiglia.de/app/webroot/img/editor/file/lisojulugabe.pdfIn PDF document text
    • https://hahapediatric.com/uploads/files/202109092337242838.pdfIn PDF document text
    • http://budapesticukraszdak.hu/userfiles/files/3986061046.pdfIn PDF document text
    • https://skykharchono.mn/editor/files/zadefajipizunuvosaveku.pdfIn PDF document text
    • http://zdrowejaja.com/Upload/file/tezin.pdfIn PDF document text
    • https://tlproduct.com/userfiles/file/tapoxuzaxopixusodu.pdfIn PDF document text
    • https://tdfstore.it/file/vurodelal.pdfIn PDF document text
    • http://ambulatorioveterinariovianello.eu/userfiles/files/diragirovodedefira.pdfIn PDF document text
    • https://rowanmkt.com/Uploads/ckfinder/userfiles/files/19734664573.pdfIn PDF document text
    • https://campermagazine.tv/public/file/4961649779.pdfIn PDF document text
    • http://dabaizhongxue.com/upload_fck/file/2021-9-1/20210901232323428620.pdfIn PDF document text
    • https://it-remarketing.pl/app/webroot/media/files/13103763607.pdfIn PDF document text
    • http://study4student.com/cache/fck_files/file/21088128445.pdfIn PDF document text
    • https://zagorjeadventureteam.hr/files/3741953543.pdfIn PDF document text
    • http://toszegisuli.hu/userfiles/file/zivavolanirinunebu.pdfIn PDF document text
    • http://le-bouquet.be/userfiles/files/juwukodigosi.pdfIn PDF document text
    • https://nieruchomosciprzetargi.pl/files/file/91522984088.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139fa2d9915d---13676363919.pdfIn PDF document text
    • https://stpm-sa.com/userfiles/file/10086548198.pdfIn PDF document text
    • http://isisthailand.org/file_media/file_image/file/70728697145.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=free+download+apk+instagramPDF 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_off0000b6af.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB6AF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cec6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCEC6 10892 bytes
SHA-256: 21b1d9e3d09bdcc8fea6e329d75d5336e51e85ffa0141fcc2c0e7117091cb114
font_02_sfnt_off0000e7c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7C5 16952 bytes
SHA-256: bee53761c9ee92684bb4793f59add7dcaf591fdc273bcf3d421f9dd8c1c7ccfa