Malicious PDF — malware analysis report

Static analysis result for SHA-256 31f72a4d17736230…

MALICIOUS

PDF

100.0 KB Created: 2021-06-26 22:57:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 906697e5d91ed88de21be9269884f741 SHA-1: 339554d636a0b67fc13da46329a2d3f22cdf8fbd SHA-256: 31f72a4d177362309f435ef5a8fcd79d97dfc4e6778373daa497f14349cca6ba
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, with numerous URLs pointing to compromised WordPress upload directories. These links likely serve as lures for phishing attacks or to distribute further malware payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9800

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 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 https://www.booster-p.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fb74e2b472---99253057404.pdf
    • http://www.hptindia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b2183374b7---23507477652.pdf
    • https://thriveelearning.com/wp-content/plugins/super-forms/uploads/php/files/fd88d3299bec2d95956c08e5bcf04779/39407628735.pdf
    • http://stkvn.ru/wp-content/plugins/super-forms/uploads/php/files/bf2f0b2a9d5712200cfb479f2bb0c57c/zumexogelo.pdf
    • https://bednidhitraders.com/userfiles/file/48631763431.pdf
    • https://economiadecomunion.net/ckfinder/userfiles/files/278975486.pdf
    • http://plusbateria.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a2b3c14b493---68836558182.pdf
    • https://www.kiteschule-eckernfoerde.de/wp-content/plugins/formcraft/file-upload/server/content/files/160aa96495d53f---xiraxasikawowusopemas.pdf
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16078864d233f9---80262903380.pdf
    • http://evola.it/userfiles/files/jebisajifoduwa.pdf
    • http://dmn.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160c50f4b5af12---jekefitabazen.pdf
    • https://carlojans.com/cms/file/pibevujuduloxo.pdf
    • https://www.jemelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ca03956064---42801536256.pdf
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a91d5dd529a---75763110875.pdf
    • https://www.themeshcowork.com/wp-content/plugins/super-forms/uploads/php/files/93865bec6011f9dcb70c5d9176664688/paxidufisudirevagubutopus.pdf
    • https://alsterparkett.de/wp-content/plugins/super-forms/uploads/php/files/grjrumdo966a3tr44r6cj43evq/20193779999.pdf
    • https://travelstore.tn/userfiles/file/bufomuzig.pdf
    • https://comobrew.com/newsite/images/user_uploads/file/mopederename.pdf
    • http://benevolo.it/userfiles/files/wewubaveduwa.pdf
    • http://moon-villa123.com/CKEdit/upload/files/belobarofoxabazugetevu.pdf
    • https://alkalacarservice.com/public_html/userfiles/file/batuwijulatewur.pdf
    • http://app8itebarandgrill.com/admin/images/file/39654902706.pdf
    • http://metzpaintings.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a786f74399e---zuvop.pdf
    • https://ises.ca/phpsites/vertical_living/uploads/file/rexona.pdf
    • https://bibliotheque-des-arts.ch/ckfinder/userfiles/files/64349897347.pdf
    • https://archltginc.com/wp-content/plugins/super-forms/uploads/php/files/2b62da25ee7fce111087a20ee7e68b60/wenafiromomajedeb.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=socialist+meaning+in+indian+constitution
    • https://bit.ly/39zuEtf
    • 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_off00012420.bin
262aeb8286e4a1c335f185d28d671237053481fb504301888bad9a83237d6a42
pdf-font-stream PDF embedded font (sfnt) at offset 0x12420 17892 bytes
font_01_sfnt_off000151ed.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x151ED 16792 bytes
font_02_sfnt_off00016a04.bin
d657421ef814da8d89799299d6f79dac01515462a687ab7bdf08dd179dace2bf
pdf-font-stream PDF embedded font (sfnt) at offset 0x16A04 10788 bytes