Malicious PDF — malware analysis report

Static analysis result for SHA-256 4d16f732ba87434c…

MALICIOUS

PDF

87.5 KB Created: 2021-09-01 20:59:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5c520db7468a64df95d5f13fa904c04e SHA-1: e3d013196c0258801bb53fca93c6b0be180c9624 SHA-256: 4d16f732ba87434c6552efc206f46718abfebc7e1e3b123ba7e7e5e292e61cfa
164 Risk Score

Malware Insights

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

The PDF contains a large number of links hosted on various domains, many of which appear to be compromised WordPress sites. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a link farm structure, and the ML classifier and ClamAV detection strongly suggest malicious intent. The document body is heavily obfuscated, preventing analysis of its specific content, but the overall structure points to a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://caribsplash.org/wp-content/plugins/formcraft/file-upload/server/content/files/16089873d1cdee---22420539438.pdf
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/82af87221ef8fc727f5dd75a39bab74a/nopewatiguwefiko.pdf
    • https://www.hit-education.com/wp-content/plugins/super-forms/uploads/php/files/nrsnn4bj5431ovb397hm0smg21/lotirakukozije.pdf
    • http://clubmaniacr.com/campannas/file/29543314519.pdf
    • https://40parables.com/wp-content/plugins/super-forms/uploads/php/files/dc30ad21ee3894b23e268d2e20c06733/siwujukozuxiluri.pdf
    • https://sharjahcements.com/images/bulk_images/files/77068068998.pdf
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/58a6e0e5bfdf5f43d3f000db557e7e01/musevuberotalawanofepew.pdf
    • https://stakeoutllc.com/wp-content/plugins/super-forms/uploads/php/files/d769262faa2798378442d1dc298968e7/demafabunepafa.pdf
    • https://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/f6da37dc754dc97fa95ac077e7fc3f2a/petedezuxe.pdf
    • https://wentworthre.com/wp-content/plugins/super-forms/uploads/php/files/ca6130fb4b640f34f4f272af3503d382/xidelijaredijafoxaxezo.pdf
    • http://www.rkcomdesignservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098e74fa4503---najikegux.pdf
    • http://www.zopfitravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098ccc71ba04---27369634217.pdf
    • https://proia.bg/userfiles/file/41950397135.pdf
    • http://ophtalmic-overnight.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160821da34c0c1---vosobukemanit.pdf
    • http://klimagra.pl/images/wysiwyg_img/file/8297531033.pdf
    • http://jhroseclassof77.com/clients/45984/File/21951480325.pdf
    • http://vipavtoufa.ru/wp-content/plugins/super-forms/uploads/php/files/d350c59aae2f05c01d53741ff2a93dfa/zusikanufawoxigutevijus.pdf
    • https://classykitchen.pl/web/uploads/files/77748514252.pdf
    • https://www.thecandystoresudbury.com/wp-content/plugins/super-forms/uploads/php/files/2hrtm4297u5k0fcqklpv3blcvp/sunesoligowutaza.pdf
    • https://at-studio.tw/app/webroot/userfiles/files/20210805_140505.pdf
    • http://haenuri.net/ckupload/files/84494086046.pdf
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090874b57542.pdf
    • http://dailymaytrogiang.com/userfiles/files/58471454432.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=macbeth+study+guide+questions+and+answers
    • 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_off0000ef81.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEF81 16792 bytes
font_01_sfnt_off00010798.bin
ad7858b72ab65cadf6da22e97bdb3095fc188b2a047107f9e5576c364b7e98f9
pdf-font-stream PDF embedded font (sfnt) at offset 0x10798 11184 bytes
font_02_sfnt_off0001214c.bin
af408ff435b38f6db4962c29a7cbaee9646bd942f61483d190bd2db2e83c86e7
pdf-font-stream PDF embedded font (sfnt) at offset 0x1214C 17900 bytes