Malicious PDF — malware analysis report

Static analysis result for SHA-256 8943d2ff20e61d85…

MALICIOUS

PDF

72.9 KB Created: 2021-09-24 21:36:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 3a596234992cbd98fdeece226b801eca SHA-1: 9b218e451f88e42d7a9b4a62e09de935942c9457 SHA-256: 8943d2ff20e61d85b0ca0341ff3fd9b31634adb0f0a09cf77a7070777c2d4d6a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm pointing to multiple compromised WordPress sites, suggesting an attempt to distribute malicious files. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were directly extracted, the presence of numerous embedded URLs and the heuristic findings point towards a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

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 http://aihyang.com/userfiles/file/jizomajitejiwudafuda.pdf
    • http://israel-aliya.com/wp-content/plugins/super-forms/uploads/php/files/37dd87eb5e54d0c34a820c6be13aff90/xaxidexilozibetuwituzaga.pdf
    • https://fmpride.com/wp-content/plugins/super-forms/uploads/php/files/03b84ed64df35fce6e3b85c489ab15e7/xaxaxubisodosurupavi.pdf
    • https://kodcomputers.ro/2664/uploads/41918725662.pdf
    • https://cfacgroup.com/uploads/FCK_files/file/86001230893.pdf
    • http://xn--80ackbssfuieecff0e8c.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/1pv1o5b58re44ig0mhu5od6gn0/52235975323.pdf
    • http://saint-party.com/media/file/55964909713.pdf
    • https://njsolarpower.com/wp-content/plugins/super-forms/uploads/php/files/274d969f4dc0e6202f70fd05547ed896/68187981663.pdf
    • http://bbfederico2.net/userfiles/file/88861455621.pdf
    • http://synowka.pl/galeria/file/kifokavarupuwike.pdf
    • http://alacarte-grafik.de/userfiles/file/65067641077.pdf
    • http://climacom.eu/userfiles/files/40861960253.pdf
    • https://laps.pl/userfiles/file/mukidakimaf.pdf
    • https://xn--72ca1bzcdf9cg5df4n5a8cei.com/userfiles/files/ruropifirimofufolali.pdf
    • http://3qbuy.com/CKEdit/upload/files/38012865792.pdf
    • http://ordineveterinarivenezia.eu/userfiles/files/nefimukawupesa.pdf
    • https://slavica.ru/wp-content/plugins/super-forms/uploads/php/files/1ebf733b8f1dda1479c71e462dba002a/24066784286.pdf
    • https://afritransport.com/app/webroot/files/file/limox.pdf
    • http://geology.ie/wp-content/plugins/formcraft/file-upload/server/content/files/1614bd3fca38fe---pobet.pdf
    • http://kahounova.cz/userfiles/file/20190252630.pdf
    • https://mkycc4.com/kycc4.com/userfiles/files/dewesudigufemonijokanas.pdf
    • http://acmemask.com/upfiles/editor/files/rurezixitigaxivapivu.pdf
    • http://brilspa.ro/userfiles/file///81193159469.pdf
    • http://dralituncer.net/userfiles/file/27809723089.pdf
    • http://www.pro9apps.com/app/webroot/files/uploadimagesfile/68512114841.pdf
    • https://taiwan-tiaya.com/upload/tiaya_official/files/64912787217.pdf
    • https://www.truck-transport.com/ckfinder/userfiles/files/30775122089.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=gm+player+apk
    • 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_off0000b8ea.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB8EA 16792 bytes
font_01_sfnt_off0000d101.bin
804be66fdb79944a9ad7bd00b96405acb55ca4489c055d3fbe9818ee40b9da56
pdf-font-stream PDF embedded font (sfnt) at offset 0xD101 10076 bytes
font_02_sfnt_off0000e775.bin
5d61765772ab4d88f314b86fd6c4a5098eefa22b731a4b88650c28d46d6b09a0
pdf-font-stream PDF embedded font (sfnt) at offset 0xE775 17948 bytes