Malicious PDF — malware analysis report

Static analysis result for SHA-256 8872bb1ff86cc664…

MALICIOUS

PDF

99.9 KB Created: 2021-08-10 23:07:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c11b96724413fc6f4ada372ddb4b9536 SHA-1: c6aa1a25ca5d779216af4da862c029829745c6f0 SHA-256: 8872bb1ff86cc664addc9d9272cf44ccf512da05b5525024ca51950323a997f6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by a machine learning classifier and ClamAV as malicious. It functions as a link farm, containing numerous URLs that point to external resources. Several of these URLs are hosted on compromised WordPress upload directories or utilize disposable hosting, suggesting an attempt to distribute malicious content or conduct phishing operations. The PDF structure itself does not contain executable scripts, but the embedded URLs are the primary indicators of malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://billionbosses.com/ckfinder/userfiles/files/58894044289.pdf
    • https://rybczewice.pl/userfiles/file/76816448526.pdf
    • http://tscyw.net/userfiles/file/20210614055803_gfdhru.pdf
    • https://alharithiforcameras.com/ckfinder/userfiles/files/73360012872.pdf
    • https://gradeagroup.com/wp-content/plugins/super-forms/uploads/php/files/5mh59ifidhqqrvtc6d1q8uqh2j/93394566812.pdf
    • https://rajakeempat.com/contents//files/35814779007.pdf
    • http://sochi-riba.ru/ckfinder/userfiles/files/73003483727.pdf
    • https://stefandes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e96909cbed---77118149057.pdf
    • http://progfin.pl/userfiles/file/lowibobuzitatozejutodejob.pdf
    • http://www.sparkprototypes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f57783a65da---27939557637.pdf
    • http://goteneplast.se/files/images/file/174324546.pdf
    • http://savalis.ru/userfiles/file/5871476673.pdf
    • https://senzedigicraft.com/wp-content/plugins/super-forms/uploads/php/files/73f835f3c254cdd5d1061c3f5b1e96a0/zamudofuketakefowopadezam.pdf
    • https://frontlinetherapist.com/wp-content/plugins/super-forms/uploads/php/files/5bfa0286d98b9912d90e7ec8d0ccc80f/simisal.pdf
    • https://msr-hudsonproperties.com/wp-content/plugins/super-forms/uploads/php/files/0e5b800c19fcbebd9162fe4f6fa877ef/39097324612.pdf
    • https://silky.ae/images/bulk_images/files/76609165060.pdf
    • http://agriturismolescuderie.eu/userfiles/files/xozukokex.pdf
    • http://novaserv.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f3960334955---fubuliridupokajewitesi.pdf
    • https://www.reparaciondebomba.com.ar/wp-content/plugins/super-forms/uploads/php/files/9kd23aebue7schbooukeu5fuh2/53080202081.pdf
    • http://www.realisthotel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b88008877a---kixip.pdf
    • https://magazinul-de-instalatii-sanitare.ro/app/webroot/files/userfiles/files/3465950500.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=oyun+d%C3%B6nemi+ruh+sa%C4%9Fl%C4%B1%C4%9F%C4%B1+ve+hastal%C4%B1klar%C4%B1+pdf
    • http://s292376414.onlinehome.fr/datas/imgmail/file/dadagiwoki.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_off00011dc1.bin
7b015de578bd8fd2eb7e686b6fe4ad44b1d2895a14ca19937fa1ebf877d9bc54
pdf-font-stream PDF embedded font (sfnt) at offset 0x11DC1 11532 bytes
font_01_sfnt_off000138a3.bin
88f668da85c9e74c755bf5bf01d3eafbb2f8b45f6592b8a1b328a20f8a93216b
pdf-font-stream PDF embedded font (sfnt) at offset 0x138A3 19208 bytes
font_02_sfnt_off00016789.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x16789 16792 bytes