Malicious PDF — malware analysis report

Static analysis result for SHA-256 841be4c731ab7b79…

MALICIOUS

PDF

78.1 KB Created: 2021-07-02 17:42:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: aeeb477c96050ef2b2ff37628e48bed3 SHA-1: b8a6a7b91b2ab6c63e25c442bc5663d9690705c0 SHA-256: 841be4c731ab7b792a845072c796c38dbbe72ae1b794da2395cfb46e3561cb8e
164 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier indicating a high probability of maliciousness. The file contains numerous links to compromised websites, suggesting a phishing or malware distribution campaign. The presence of a 'download button' lure further supports the intent to trick users into downloading malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

Heuristics 7

  • 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.
  • 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 https://archism.ru/uplcv?utm_term=factors+sums+for+class+5
    • http://banlinhkienlaptop.com/userfiles/file/kuwesegaf.pdf
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/d1803d84465a51681c1dbd6e66030819/fudajoxedanomoxasoluvanuf.pdf
    • https://walkandsmile.com/userfiles/file/77033419619.pdf
    • https://burkina-businessschool.com/business_school/uploads/file/85078427640.pdf
    • http://geostudio.eu/userfiles/files/wakupako.pdf
    • https://ceral.pl/ceral/pliki/file/19929730373.pdf
    • http://highendschmiede.de/highendfiles/file/52341409207.pdf
    • http://bubblesoflove.net/wp-content/plugins/formcraft/file-upload/server/content/files/1608b6f11e9666---pusiwurafegejezemi.pdf
    • https://www.jahnigterbraak.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a0770b5f3ba---wapazonuzepiwuguvoze.pdf
    • http://soflacops.com/clients/83266/File/rubikomitotidagaxawir.pdf
    • http://insidethedigitaltrend.biz/userfiles/file/7875367860.pdf
    • http://atlantichomeportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/160dda2235eba7---44613885735.pdf
    • https://www.mercedesbenzofaustinservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073771b566bb---38290123358.pdf
    • http://quickvideo.nl/userfiles/file/tadofiwasajarofaru.pdf
    • http://posekatzahradu.cz/files/file/vifoxelewurazanefilo.pdf
    • http://ccspatti.org/userfiles/file/dorimesepabodomek.pdf
    • http://canyonoaksmtg.com/~duckdi5/canyonoaksmtg.com/content/file/97146259343.pdf
    • http://brodart01.com/wp-content/plugins/super-forms/uploads/php/files/rj694aqjekfa841tr62nnsesdo/medoxutara.pdf
    • https://expresstestingatl.com/wp-content/plugins/super-forms/uploads/php/files/81f84128bcf678ba6eb887f736fdf873/75433480233.pdf
    • http://fresh-j.info/images/uploadedimages/file/77703702424.pdf
    • https://www.heainc.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad3eaa20c40---29666473636.pdf
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608d42230b19f---nudiwavi.pdf
    • http://cbelmira.com/wp-content/plugins/super-forms/uploads/php/files/ebjs16h3iih174d1sga6d4p6i2/tawewiwu.pdf
    • http://sieuthibds.net/images/files/pojorurewesujoxakolova.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_off0000ceb5.bin
4f4cc79307a1b62124299be02d59bcc8f46abe5a413b9e0b3c62af56623ccba9
pdf-font-stream PDF embedded font (sfnt) at offset 0xCEB5 17244 bytes
font_01_sfnt_off0000fbd5.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFBD5 16792 bytes
font_02_sfnt_off000113ec.bin
b37e2f8f013abea8e19743e7b99b96aac820042f880f37128c21b8f22dd387aa
pdf-font-stream PDF embedded font (sfnt) at offset 0x113EC 10380 bytes