Malicious PDF — malware analysis report

Static analysis result for SHA-256 a3849ff3569e8c76…

MALICIOUS

PDF

85.6 KB Created: 2021-07-04 02:44:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 976899b49d707f9bc070c7ff203e43a5 SHA-1: 93821c025ba32cd1ea3280b0c505ac87d362602c SHA-256: a3849ff3569e8c766cb1769106fc22d155fa2ef3c3ffc1cdca7913dfe197d49d
164 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically identified as Pdf.Phishing.Trojan. Heuristic analysis revealed it functions as a link farm, directing users to compromised WordPress upload storage and other disposable hosting sites, likely to facilitate the download of further malicious content. The presence of a download button lure reinforces the deceptive nature of the document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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
  • 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.
  • 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 http://www.findvoters.com/userfiles/file/fozovubasig.pdf
    • http://festivaldeliteraturadepereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bff22722297---nalezul.pdf
    • http://biancoacolori.it/userfiles/files/49214240220.pdf
    • http://www.1atlanticfunding.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606e98d98841f---6122167513.pdf
    • http://endustriyelkiralama.com/wp-content/plugins/super-forms/uploads/php/files/a6f1em3j7fkvl5nsehold871q0/vuvixawavagegokutaditu.pdf
    • https://toolsatool.com/userfiles/files/wewosodi.pdf
    • http://gemculture.com/userfiles/file/87171132968.pdf
    • http://acecaalcoy.com/userfiles/file/vivimukagudemufi.pdf
    • https://jaiminsales.com/ckfinder/userfiles/files/gazijovipazotiwuna.pdf
    • http://af.ssla.ru/images/fornews/files/kugejud.pdf
    • https://equinox-e.com/upload/files/68955600685.pdf
    • http://rajeshjshahani.com/clients/d/de/defaee86e9f1fedea086b53a5072ac2c/File/sogepeku.pdf
    • http://diversecityuk.com/userfiles/file/33902269779.pdf
    • https://guruamardaspublicschool.com/userfiles/files/fipop.pdf
    • http://www.iqubz.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a9cd3b6339---vukukagobalufafe.pdf
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b26a275a829---jovojowafusabu.pdf
    • https://alismobile.co.uk/wp-content/plugins/super-forms/uploads/php/files/8311b754fb7d62326afbd29171e3af8f/wenopazejaf.pdf
    • http://ekachaiguitarist.com/ckfinder/userfiles/files/rewawotejedazovusuleni.pdf
    • https://www.dolphinrfid.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cb8c6cf1ded---26682208707.pdf
    • http://modnyi-buket.ru/uploads/files/visapebeded.pdf
    • https://messianic.live/wp-content/plugins/super-forms/uploads/php/files/648aaf56949f6e8eb49865a76047f348/naxab.pdf
    • https://empylean.com/wp-content/plugins/super-forms/uploads/php/files/cd6v6avjhv0hh1uc9bp3d73sft/donitox.pdf
    • http://alptw.com/images/files/sezasabixukel.pdf
    • http://perlawarmii.pl/userfiles/file/nuzebimefo.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=converter+pdf+to+kindle+ebook
    • 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_off0000edb9.bin
93e5b6971b0b819e170d4e1a7efab8b925d00e5bdc5fea505d8a751f9cbdba9c
pdf-font-stream PDF embedded font (sfnt) at offset 0xEDB9 10492 bytes
font_01_sfnt_off00010575.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10575 16792 bytes
font_02_sfnt_off00011d87.bin
9c6acef61074c538e77c384fabef859fc28cafcfd06f53e86ab529941a10ce3b
pdf-font-stream PDF embedded font (sfnt) at offset 0x11D87 16812 bytes