Malicious PDF — malware analysis report

Static analysis result for SHA-256 a177b6f4c77c8152…

MALICIOUS

PDF

71.4 KB Created: 2021-09-25 03:56:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d215c4658a50c5783581a258532611e2 SHA-1: ba8686da9266492c720d68e4e4a251a31e70ee5d SHA-256: a177b6f4c77c815245a39e31fcef750f955f082ad4dafb3b8e9ce804f1455999
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous links to external websites, many hosted on compromised or disposable domains, indicating a link farm or phishing lure. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or distributing further malware. No scripts were extracted, but the structure and URL patterns are consistent with a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://huntic.ru/uplcv?utm_term=how+to+find+saved+links+on+android
    • http://eluvial.com/sites/all/sites/eluvial.com/files/jizerudosidudokuwamegujif.pdf
    • http://www.holzbau-hoelzl.at/wp-content/plugins/formcraft/file-upload/server/content/files/1612f142f528f6---mulune.pdf
    • http://doudou.tw/userfiles/files/lejegisur.pdf
    • https://winpoasia.com/ckfinder/userfiles/files/walanazosevasojogaza.pdf
    • http://saigondome.com/uploads/userfiles/file/sabarixalefos.pdf
    • https://ncfouting.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f359a0e497---24624651567.pdf
    • https://smartcirclegroup.com/userfiles/file/39350167947.pdf
    • http://gndpta.eu/news_objects/files/tavexobe.pdf
    • http://rideabikenews.com/user_img/files/3150614990.pdf
    • http://www.swaving-stalinrichting.nl/ckfinder/userfiles/files/pukurozijenuviropexu.pdf
    • http://opuspoint.com/ckfinder/userfiles/files/39204555372.pdf
    • http://elitaliaweb.it/upload/file/nusakamur.pdf
    • https://1877painters.com/FCKeditor/file/3865664325.pdf
    • http://www.badischer-kunstverein.de/ckfinder/userfiles/files/suzopoluvutipezixabowise.pdf
    • http://www.hollyskauaicondo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f4d58da0cb---mujofigufo.pdf
    • https://pixel.bg/img/file/17140228180.pdf
    • http://kibbkw.com/uploads/file/ledarovatewenageja.pdf
    • https://cam-ceeds.org/ckfinder/userfiles/files/52635803253.pdf
    • https://xn--p3t29jo1ed4o4xw.tw/upload/files/bonebunoduwezinerebow.pdf
    • http://lyzph.com/userfiles/file/Fl202109242016594394.pdf
    • https://zenit-npk.ru/files/file/86131728342.pdf
    • http://vuonlan.vn/data/upload/files/91565010479.pdf
    • https://www.yoursurveysurveyors.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613e5a67803d4---rugilevagagokizuravabube.pdf
    • http://zhouzhuanx.com/v15/Upload/file/20219238996678.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_off0000b3a6.bin
dde3958bfc62845c1f81ab97c103e9b94c58b65f990004a336bc401a0ef28b99
pdf-font-stream PDF embedded font (sfnt) at offset 0xB3A6 16912 bytes
font_01_sfnt_off0000df71.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDF71 16792 bytes
font_02_sfnt_off0000f788.bin
d5487177cc502acd97b76414d4ee161759e54cf5ec36aad281a446a6b58dafdf
pdf-font-stream PDF embedded font (sfnt) at offset 0xF788 10580 bytes