Malicious PDF — malware analysis report

Static analysis result for SHA-256 8b4e592ccdad605e…

MALICIOUS

PDF

70.2 KB Created: 2021-09-25 16:33:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 3d114394320a101148c719ea6d58bb50 SHA-1: 489b328b59ae1feda13af2f1ff71bf08e2dfbc43 SHA-256: 8b4e592ccdad605e8f1261748b77d3b58821eaec275fa3255afa2a93950a6bd1
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs that point to a link farm hosted on disposable domains, a common tactic for distributing malicious content or conducting phishing campaigns. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' strongly indicates this malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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=android+app+projects+with+source+code
    • http://aroma-es.site/yamituki-n/uploads/files/93155314561.pdf
    • http://archetipoingegneria.it/userfiles/files/4382675940.pdf
    • https://cr2tek.com/userfiles/Proj_Name/files/66336826137.pdf
    • https://krusomying.com/data/file/famiguzifavomimigesuvim.pdf
    • https://aymfly.com/aym_image/files/13435750837.pdf
    • http://www.520amis.com/upload/files/52080488111.pdf
    • https://karolinanowak.com/userfiles/file/sukozugajofasew.pdf
    • https://mindweave.co.uk/wp-content/plugins/super-forms/uploads/php/files/42tlmc2f2de1v71hprq9q0oq09/35893745944.pdf
    • http://www.boldino-hotel.com/ckfinder/userfiles/files/80201117410.pdf
    • https://eliteplacementagency.com/uploads/files/pumizos.pdf
    • http://rigosarchitects.gr/userfiles/file/xizugirofarapagikiju.pdf
    • http://squarcialupirelaxinchianti.com/writable/public/userfiles/file/vuwoguxavepuwovegipi.pdf
    • https://ashasuchikala.com/ckfinder/userfiles/files/52978002948.pdf
    • http://www.sandipmallick.com/fckimages/file/1631695874.pdf
    • https://wangwangcamp.com/uploads/files/202109080619325931.pdf
    • http://mylodge-naoshima.com/images/blog/file/vegoletonatelojez.pdf
    • https://limsurdua.com/contents/files/lasujususidulizow.pdf
    • https://vinacoma3.vn/userfiles/file/95380210762.pdf
    • http://mywayrtk.org/userfiles/file/nozadusewexuvalanoxiwige.pdf
    • https://howardsteeves.com/wp-content/plugins/super-forms/uploads/php/files/512700408c03076095a8549e7b32d052/nopawulonexinarilipesa.pdf
    • http://demo-enriquemora.shopcloud.es/ckfinder/userfiles/files/7454960199.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ae47.bin
80c828c8b1e87f1408b3ef91e3cce5f3030a9592e9cac9a839cab75b7a1eba6c
pdf-font-stream PDF embedded font (sfnt) at offset 0xAE47 10864 bytes
font_01_sfnt_off0000c758.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xC758 16792 bytes
font_02_sfnt_off0000df6a.bin
80f78e8ab08fa4ee1fc971fb4d7b0ee4e029fda548a837447b535c27fac64740
pdf-font-stream PDF embedded font (sfnt) at offset 0xDF6A 17144 bytes