Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f861cea1ef0cd7d…

MALICIOUS

PDF

83.7 KB Created: 2021-07-26 11:06:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 60151f98a172889241c586267a19ed51 SHA-1: e8dec8cdd43b1738195b7e7bac7d10bc3707d9ad SHA-256: 8f861cea1ef0cd7d8e7de4c48c7c42fb0e85c0b2d5eda03aecc639675de8659c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF contains numerous links pointing to various domains, many of which are hosted on compromised CMS upload directories, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery. Although no scripts were explicitly extracted, the structure and URL patterns are consistent with PDF-based malicious campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://ccforum.kr/uploads/file/1625196608.pdf
    • http://elonsummerstorage.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a21f9a1f0d---repobilorugix.pdf
    • https://qamarapps.com/wp-content/plugins/formcraft/file-upload/server/content/files/160fb38faea581---80175024550.pdf
    • https://3dreamstudios.com/wp-content/plugins/super-forms/uploads/php/files/84ba81244d0ae6d323d1d788c05d31ce/nafusekoxilego.pdf
    • http://branonperformance.com/ckfinder/userfiles/files/roxirarolivolekadame.pdf
    • http://sanarina.de/ckfinder/userfiles/files/31502282060.pdf
    • http://elementsgogreen.com/userfiles/file/65328832219.pdf
    • https://victory-agency.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080b5892b3f1---wabego.pdf
    • http://raunlarose.us/wp-content/plugins/formcraft/file-upload/server/content/files/160a2a6ef34d73---mebexifemex.pdf
    • http://flexicourse.cz/res/file/369296455.pdf
    • https://gw21.ch/uploads/userfiles/file/1346472512.pdf
    • http://ccadl.com/files/20210714110219.pdf
    • http://www.ausafrica.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160a434e914d83---zugufufebekuzolomemusag.pdf
    • https://asthasupermarket.com/userfiles/file/lixudutumirudufujew.pdf
    • https://weinquartier.at/wp-content/plugins/super-forms/uploads/php/files/a817f8a41623cd91500fe0460d80c0ea/vedejevetob.pdf
    • http://www.medical-psychology.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160bff71cbffce---81514468680.pdf
    • https://misionesmedellin2030.com/wp-content/plugins/super-forms/uploads/php/files/utj1enjrpsc9sdj5pv056gouis/tapatobapupedekizobojadi.pdf
    • https://rdsdealers.com/ckfinder/userfiles/files/xukamozawafufikewigarazi.pdf
    • http://ytovietnam.net/ckfinder/userfiles/files/gadugipik.pdf
    • http://regmac.net/userfiles/files/mufat.pdf
    • http://bochosushi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160778ae07b6b8---rifazuv.pdf
    • https://pcstaiwan.com/ckfinder/userfiles/files/23132672304.pdf
    • https://mwasafat.com/uploads/files/fotiwezupemojexixupedi.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=comparatives+and+superlatives+exercises+english+hilfen
    • 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_off0000e38f.bin
2b05f5a002ab69a8340d9560892788ee492fb8bc8077241c2033b8abbff799ea
pdf-font-stream PDF embedded font (sfnt) at offset 0xE38F 11368 bytes
font_01_sfnt_off0000fdf4.bin
cf22c6ca8e305cb88f93f9e59ae4a6a61c89812282ee901d0039dc6a8bc56a4b
pdf-font-stream PDF embedded font (sfnt) at offset 0xFDF4 16540 bytes
font_02_sfnt_off00012852.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12852 16792 bytes