Malicious PDF — malware analysis report

Static analysis result for SHA-256 fd76fe660b54d281…

MALICIOUS

PDF

100.7 KB Created: 2021-07-18 09:26:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 73b209f0125608dde709cae9a4a35746 SHA-1: 4aed5b81a1002e2be345c1bdf428b2f1e733bf49 SHA-256: fd76fe660b54d28152a717bfab6573853b370d49eb8a1455cb695e5f13fa6cd1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains a link farm with numerous URLs pointing to compromised websites and disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the structure and embedded URLs suggest an attempt to lure users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9910

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://sdyh.gr/wp-content/plugins/super-forms/uploads/php/files/jlni05gm8mkfqrh0625lb4vj52/linokevufudoxuwudovizuf.pdf
    • http://www.cuadernos.in/wp-content/plugins/formcraft/file-upload/server/content/files/16085cc404a56f---78283147161.pdf
    • http://montaze.org/democms/userfiles/file/37317510379.pdf
    • http://archinfo.ru/uploads/file/91848025698.pdf
    • https://viajespereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a5b773c7125---mowefepemapidejevamuw.pdf
    • http://www.etoiles-recrutement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d2df90c02e---vazudineretekigunenuga.pdf
    • https://www.masismarketing.com/wp-content/plugins/super-forms/uploads/php/files/d0467e4b8dc0bcbf5f942e2cf0fbc061/tawazi.pdf
    • https://studiorampinelli.com/file/gurulizelutasutu.pdf
    • https://locktactyuma.com/ckfinder/userfiles/files/65092499583.pdf
    • http://mtprospectbaptist.org/clients/7/74/74f10a8404da00fab064704771972c19/File/31023005030.pdf
    • http://www.whirlpool-beachcomber.at/wp-content/plugins/formcraft/file-upload/server/content/files/1606f89380764a---47601802887.pdf
    • https://www.karenlovelee.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a419af79499---43558027131.pdf
    • http://thaoduocquyhiem.com/userfiles/image/file/22400077646.pdf
    • http://hattrick-sports.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a5a24f389f1---misoti.pdf
    • https://www.chartsunlimited.com.ph/wp-content/plugins/formcraft/file-upload/server/content/files/1609a05c5308fe---11852660034.pdf
    • http://broadgatecapital.com/userfiles/file/retowesepebinitezitewiz.pdf
    • http://asja-doll.ru/userfiles/file/zememadepitekuwojeloge.pdf
    • https://controlcert.se/wp-content/plugins/formcraft/file-upload/server/content/files/160a8d90a43e4b---26672544333.pdf
    • https://www.d-table.com/wp-content/plugins/super-forms/uploads/php/files/4201bed5dae9922e977325bdf27ead14/nolezirivatinejago.pdf
    • http://kronikarp.pl/ckfinder/userfiles/files/3903609370.pdf
    • https://ietc-oman.com/userfiles/files/25913207351.pdf
    • http://bhk-aindling.de/userfiles/files/72559441301.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=essentials+of+vlsi+circuits+and+systems+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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010a0a.bin
5d18997ea90413345dbb4ed1f23a5736bed52f45ee8c19ed3b39679e892f5605
pdf-font-stream PDF embedded font (sfnt) at offset 0x10A0A 11044 bytes
font_01_sfnt_off000123ce.bin
407841d170a344e6db8d6b61f282472220382edc8b08cbd836eadf3e42eccc31
pdf-font-stream PDF embedded font (sfnt) at offset 0x123CE 21180 bytes
font_02_sfnt_off00015785.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x15785 16792 bytes
font_03_sfnt_off00016f96.bin
00b1f632e8afe72716c8bcdb76b7901b56c060d1dc0f96f3f5c1b8373b85735b
pdf-font-stream PDF embedded font (sfnt) at offset 0x16F96 16140 bytes