Malicious PDF — malware analysis report

Static analysis result for SHA-256 1f8f9da1bac70893…

MALICIOUS

PDF

80.7 KB Created: 2021-09-20 01:23:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: f077b1bb53562a8f023e3ed1fe0030b6 SHA-1: a3c36756b868841b320c9dafbd2e7a3c83247f89 SHA-256: 1f8f9da1bac70893e51e4433fea578a74b048d97912127bc412ec93eed595d52
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The presence of multiple external URIs, including one pointing to an IP address, and the heuristic identifying it as a link farm on disposable hosting suggests a phishing or malware distribution attempt. The document body, though heavily obfuscated, contains metadata indicating it was generated by wkhtmltopdf, a tool often used to create PDF documents from web content, further supporting the lure of a downloadable file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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
  • Clickable URI points to raw IP address medium PDF_URI_IP_LITERAL
    PDF contains a clickable HTTP(S) action whose host is a literal IPv4 address. Legitimate documents normally link to named domains; raw-IP destinations are common in disposable phishing and malware-delivery infrastructure.
  • 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.
  • 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://wastran.ru/uplcv?utm_term=pdf+to+excel+using+vba PDF link annotation
    • https://makojudo.pl/zdjecia/fck/file/19465368824.pdfIn PDF document text
    • http://cukrarska-vyroba.cz/UserFiles/File/21239761548.pdfIn PDF document text
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/5bae7c394390bf2f7a024fb1ba3acc4d/99729735429.pdfIn PDF document text
    • http://soeurs-scjboran.fr/soeurs/upload/files/87061634784.pdfIn PDF document text
    • http://nessium.net/userfiles/file/gigaziwagopelabineje.pdfIn PDF document text
    • http://benthanhsgfarm.net/images/uploads/files/bazisomadevepemib.pdfIn PDF document text
    • http://sarljarry.com/userfiles/file/8130149931.pdfIn PDF document text
    • http://chistogood.ru/admin/ckfinder/userfiles/files/gagimijijovikimibosirot.pdfIn PDF document text
    • http://jilienjrubin.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/wegejaxowegat.pdfIn PDF document text
    • https://bak.vn/upload/files/13992380923.pdfIn PDF document text
    • http://www.frank-diagn.hu/userfiles/files/43671431200.pdfIn PDF document text
    • http://3bbb.fr/ckeditor/upload/files/xoxexajadepanivaso.pdfIn PDF document text
    • http://cutyoursupport.com/userfiles/file/tuxivemaligutemuxaden.pdfIn PDF document text
    • http://wabasnb.com/files/fckeditor/file/137855541761404e3b41407.pdfIn PDF document text
    • http://wxmx.cn/upload/ckimg/files/202109081952019322.pdfIn PDF document text
    • http://hpcad.pl/Upload/file/goledogejawimojiwukesovel.pdfIn PDF document text
    • http://79.170.40.182/boothtastic.com/wp-content/plugins/formcraft/file-upload/server/content/files/161447290148fb---lawatarutiwavox.pdfPDF link annotation
    • https://arerp.kr/data/file///buwefekagozuwuf.pdfIn PDF document text
    • http://hidropro.hu/upload/67393472063.pdfIn PDF document text
    • http://seghers.kr/data/editor/file/15477106736144ca2ddea3f.pdfIn PDF document text
    • http://hanyuchina.com/upload/files/13390052439.pdfIn PDF document text
    • https://beysukonaklari.com/ckfinder/userfiles/files/xanebumisatipewesekesu.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_off0000d548.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD548 17848 bytes
SHA-256: 14145acb7d2714bd63d4cd6b47a1318f25eeccdb3f524be9a39394c786165157
font_01_sfnt_off000103da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103DA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011bf1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BF1 10960 bytes
SHA-256: 2210ec67e3c5ab8597e7a6ca491ec933325c13fbcd470c16934d6904e0c46f98