Malicious PDF — malware analysis report

Static analysis result for SHA-256 fdecd435565d6c4f…

MALICIOUS

PDF

87.5 KB Created: 2021-06-26 17:23:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: f5ff2df49b811612c135a7348fd7dec8 SHA-1: 4912a4c69fe3240292a48c27ba8f1ff29ffd9023 SHA-256: fdecd435565d6c4fa339597e9f82c87206dfa99995ed2571596be49637e70517
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites acting as link farms. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or distributing further malware. The document body is heavily obfuscated and unreadable, providing no direct content clues.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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://apexforestservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160945d7dd7b25---80857007784.pdf In PDF document text
    • https://www.lokalesichtbarkeit.de/wp-content/plugins/super-forms/uploads/php/files/s8c5omn81gv4s79k4pqbgg2enr/nugik.pdfIn PDF document text
    • http://khiconghoixuancong.com/Khicong/admin/userfiles/file/nasagonazutiburonenofaz.pdfIn PDF document text
    • http://mppscstudy.com/admin/usercontent/file/50193406500.pdfIn PDF document text
    • http://www.atrium-tuiles.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a290abf17dd---92085294552.pdfIn PDF document text
    • http://davidhammerstein.org/userfiles/file/28472282527.pdfIn PDF document text
    • http://amako-ra.com/wp-content/plugins/super-forms/uploads/php/files/c9c4cfd592aefca7ec61a770f33638e6/27013101349.pdfIn PDF document text
    • http://anaminfo.com/attachfile/file/85313146444.pdfIn PDF document text
    • http://angelojrobles.com/admin_initial_test/userfiles/file/vojufoxuxejamufavifa.pdfIn PDF document text
    • http://elonsummerstorage.com/wp-content/plugins/formcraft/file-upload/server/content/files/160843e481df5f---visumafoxubibevijovubifuf.pdfIn PDF document text
    • https://afayl.com/userfiles/file/wawidunurali.pdfIn PDF document text
    • https://bikinibody.be/wp-content/plugins/super-forms/uploads/php/files/ae45kdkqq82iapo87oomd1sqps/85762168926.pdfIn PDF document text
    • http://sieckultury.pl/wp-content/plugins/super-forms/uploads/php/files/9e4a1043e9764f67e76cbc83ec020e28/42491814842.pdfIn PDF document text
    • https://denimder.org/resimler/files/budusokevabasod.pdfIn PDF document text
    • https://dongytueduc.com/wp-content/plugins/super-forms/uploads/php/files/d84n2tdvap874f5alo63h7pbrv/salelazafelupuvuzofe.pdfIn PDF document text
    • http://www.mondzorgvesa-voorschoten.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1609490ac9839e---bizeni.pdfIn PDF document text
    • https://www.davidcosz.de/wp-content/plugins/super-forms/uploads/php/files/npv43f0lu12k33i695v8t7mumo/dovijotu.pdfIn PDF document text
    • https://teplitsyoptom.ru/wp-content/plugins/super-forms/uploads/php/files/6e0a7a2b00afad70f25fffd3ac3a535b/57686482223.pdfIn PDF document text
    • https://vernadoc.com/wp-content/plugins/super-forms/uploads/php/files/0750bd9d9dcf79c28a41053bcd3badcd/22893442561.pdfIn PDF document text
    • https://www.medipratik.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078b4b0afec9---9682902166.pdfIn PDF document text
    • https://ecobox.eng.br/wp-content/plugins/super-forms/uploads/php/files/j1i7tumlujf20oo4hm0er7sd4k/velovujiwogitoguvajepila.pdfIn PDF document text
    • https://yarsan.ru/wp-content/plugins/super-forms/uploads/php/files/b2f3f21acf77d4205c71108f6a69b6ca/1588360909.pdfIn PDF document text
    • http://diencohoanghuy.com/media/ftp/file/21406193378.pdfIn PDF document text
    • https://veglifekc.org/wp-content/plugins/super-forms/uploads/php/files//selonipazasowikabebu.pdfIn PDF document text
    • http://mu-rrrc.com/userfiles/file/rinuroxubanagosige.pdfIn PDF document text
    • http://0-50.ru/userfiles/file/16352113848.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=how+do+ants+get+wingsPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f4fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4FC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010d13.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D13 10352 bytes
SHA-256: a507c89e919d7d44bfd177751cc2aaeb78bb1795e35eb261cff21876736c4538
font_02_sfnt_off0001245e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1245E 16600 bytes
SHA-256: 19631f6093ac3b381cc1a53adbb9d8cc660ebad9258ac57cb232236095508d27