Malicious PDF — malware analysis report

Static analysis result for SHA-256 8499d3a5bbc78d4b…

MALICIOUS

PDF

75.2 KB Created: 2021-08-19 17:03:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6280dad5b742f5cef5645bba5899ec14 SHA-1: a8bdf1328b0ce3bad6703209f5ba68096af9c618 SHA-256: 8499d3a5bbc78d4b49bda8ef246208f2c8e9ec3fe6d169244111dbe69044d408
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs pointing to various websites, many of which appear to be compromised or disposable hosting. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware delivery. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' suggests the document's primary purpose is to act as a link farm, potentially to bypass security measures or distribute malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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 https://crewmak.ru/uplcv?utm_term=circles+arc+and+angle+measures+worksheet+answers
    • http://www.bestlifepolicy.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1606d077c14d83---43440063954.pdf
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607c134838388---kojowewewiz.pdf
    • https://tappowine.com/file/vivubagivikumowasogipo.pdf
    • http://urparitet.ru/admin/ckfinder/userfiles/files/41281289141.pdf
    • http://xn--l3chcucnqd9c0eua7b1k.com/user_img/files/gomajaninuritanajilaxim.pdf
    • https://www.myjamaicais.com/wp-content/plugins/super-forms/uploads/php/files/bc802a48d0a03fe25842a07b65a209e9/bekuberomuvujere.pdf
    • https://mingyi-lock.com/data/file/userfiles/files/venezifezore.pdf
    • http://perseverance.cyou/updatefiles/file/30372068552.pdf
    • https://123kozijnofferte.nl/wp-content/plugins/super-forms/uploads/php/files/f9dov1m5rrr7sa4fvndhev6iq7/96474834956.pdf
    • https://www.physioaktivkramer.de/wp-content/plugins/formcraft/file-upload/server/content/files/160bfbfcc4cf70---91070538698.pdf
    • http://outspokenholland.com/userfiles/fckFile/20210801175631.pdf
    • http://wakingbeauty.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c5bf3c6bbc---10338568482.pdf
    • https://markiza-trade.ru/admin/ckfinder/userfiles/files/92249170517.pdf
    • http://bronia.org/userfiles/file/17164395066.pdf
    • https://thuaphatlaihanoi.net/uploads/files/9766059423.pdf
    • https://immo-cjeanpaul.lu/userfiles/files/kexekirababiwodinutosesam.pdf
    • http://www.adatechotomasyon.net/wp-content/plugins/formcraft/file-upload/server/content/files/160c3822439ec4---9244010690.pdf
    • https://majorsagilekvaros.hu/uploads/file/roxugar.pdf
    • http://www.sparkprototypes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c750e20963b---tajopoxubirigi.pdf
    • http://wakingbeauty.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c6f9497e2ce---16235980600.pdf
    • https://www.ccps.mx/wp-content/plugins/super-forms/uploads/php/files/511ad6c70c38cd6ad6fe26c5822442d3/29967693305.pdf
    • http://tuderprogettazione.it/userfiles/files/65010170465.pdf
    • https://goldenparadisestsimons.com/wp-content/plugins/super-forms/uploads/php/files/07cc0d0a5d15d2a11e32efbbec2d4975/97208664902.pdf
    • https://robinio.de/wp-content/plugins/super-forms/uploads/php/files/t7li3iedih99ac6mj4cs4h9eaf/mavumajudajagugosituwotox.pdf
    • http://maxitelt.no/wp-content/plugins/formcraft/file-upload/server/content/files/16094c64167050---5641996599.pdf
    • https://agsposure.org/wp-content/plugins/super-forms/uploads/php/files/4682589c618fb6544c8c73740f058e09/55762301937.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_off0000c3c2.bin
84679eba73b5d57aed81c28f93cb5843749bc35dc209a9ba81c01d79c836e3a5
pdf-font-stream PDF embedded font (sfnt) at offset 0xC3C2 16068 bytes
font_01_sfnt_off0000ed45.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xED45 16792 bytes
font_02_sfnt_off0001055c.bin
d4b89c6ca32a06356ff56abcf00964d4a9615e3d583d6dec192274bca0761b53
pdf-font-stream PDF embedded font (sfnt) at offset 0x1055C 11128 bytes