Malicious PDF — malware analysis report

Static analysis result for SHA-256 89eb4e51d6efceed…

MALICIOUS

PDF

86.7 KB Created: 2021-09-18 04:17:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: aabfbcc310d95f4bb53a184f4ea314cb SHA-1: 6812edbd6ef4d2ba15953839284ff83508738158 SHA-256: 89eb4e51d6efceed4b16b62fff72e3b49b483e82ef580b54db081baa8e374ac0
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as a malicious PDF by multiple heuristics and a ClamAV detection. It contains numerous external links, with a high-confidence heuristic indicating a link to an algorithmically-generated URL, suggesting a phishing or malware distribution attempt. The ML classifier also strongly flagged this PDF as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9979

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://kechengchem.com/upload/files/gijejolemuwowek.pdf In PDF document text
    • http://avesta-hmora.boj.se/uploads/userfiles/files/78744746459.pdfIn PDF document text
    • https://indirimlipin.com/calisma2/files/uploads/59703922614.pdfIn PDF document text
    • http://jeanthompson.nl/ckfinder/userfiles/files/pedidozuvaw.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/161350fa709083---rarixewa.pdfIn PDF document text
    • http://wonikquartz.com/upload/editor/file/1630916478.pdfIn PDF document text
    • https://cryptoshift.be/anaeter_capital/siteadmin/userfiles/files/30524859093.pdfIn PDF document text
    • http://www.euro-fly.eu/userfiles/files/buvokenumedavilobemevo.pdfIn PDF document text
    • https://aslimitada.com/userfiles/file/35434352299.pdfIn PDF document text
    • https://thaibamboorestaurant.ca/phpsites/bard_ford/uploads/file/8012717892.pdfIn PDF document text
    • http://ambulatorioveterinariobubiniregini.eu/userfiles/files/liverikedum.pdfIn PDF document text
    • http://fotografieindex.nl/images/uploads/kadevupopijijebepimipa.pdfIn PDF document text
    • http://ackerviewguesthouse.com/userfiles/file/31667342830.pdfIn PDF document text
    • http://closehorses.com/userfiles/file/82989101665.pdfIn PDF document text
    • http://rosg.net/sa_upload/userfiles/file/20210913164543.pdfIn PDF document text
    • https://bakwanudang.com/contents/files/javusepuvax.pdfIn PDF document text
    • http://status.cz/UserFiles/File/7391864405.pdfIn PDF document text
    • http://birizgardenhotel.com/userfiles/file/42858301295.pdfIn PDF document text
    • http://radekslodkiewicz.pl/files/file/vawigexerepovet.pdfIn PDF document text
    • http://limeitec.com/upfiles/editor/files/1771273893.pdfIn PDF document text
    • http://s-pack.kr/userfiles/file/20210914133610.pdfIn PDF document text
    • http://klusjesindex.nl/images/uploads/17090565052.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=adb+shell+su+without+rootPDF 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_off0000f0c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0C0 17176 bytes
SHA-256: c493971afa6cd019fab35fe77cab7f3c9d844f3c3d0fd8a2737e09033f2b7982
font_01_sfnt_off00011dd6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DD6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000135ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x135ED 10384 bytes
SHA-256: c6e01ed0856f0ae8fa014c1cefa3c713ef48048be9b28767911ca1ab57fc1952