Malicious PDF — malware analysis report

Static analysis result for SHA-256 fcc902d82aa50a99…

MALICIOUS

PDF

83.4 KB Created: 2021-08-25 03:11:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 3d66e5164cc4b3050e7b8494650bdffa SHA-1: 5823a6d751d6904ef9cb7d6df150c5f29390a1f9 SHA-256: fcc902d82aa50a99712eeaf7d68faa13e7d51082d40e65807b14e5816e2a5e92
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with multiple URLs pointing to compromised WordPress upload directories. The presence of embedded URLs and the nature of the heuristics suggest an attempt to lure users to external malicious sites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://bizdrive.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/160afce3383d78---bapuzufafubo.pdf In PDF document text
    • http://nowyhotelik.pl/userfiles/file/94424092508.pdfIn PDF document text
    • http://vudafrique.com/wp-content/plugins/super-forms/uploads/php/files/dca4dfe28f33218a6b3bd2e217349fbf/vugusefelotiturezat.pdfIn PDF document text
    • http://ippon.lv/uploads/File/zuvewijudorekiburi.pdfIn PDF document text
    • http://chinazzjx.com/d/files/35794456752.pdfIn PDF document text
    • http://namngonviet.vn/user-/files/munipexodagowuxaba.pdfIn PDF document text
    • https://oneremote.ru/wp-content/plugins/super-forms/uploads/php/files/4a7fbe3c0dd754d1401f989363c72dbe/pevap.pdfIn PDF document text
    • https://glasschneider.koeln/wp-content/plugins/super-forms/uploads/php/files/61r88vfum3l677sot3elhleodv/25652308803.pdfIn PDF document text
    • http://friluftsgruppen.se/wp-content/plugins/formcraft/file-upload/server/content/files/160b9a3820737d---73535584398.pdfIn PDF document text
    • http://surtek.biz/image/files/20150114_162058.pdfIn PDF document text
    • http://girc.ncue.edu.tw/ckfinder/ckfiles/files/68995305370.pdfIn PDF document text
    • http://pngroup.pl/ckfinder/userfiles/files/viragomiriw.pdfIn PDF document text
    • https://holzhaus-suedtirol.it/wp-content/plugins/formcraft/file-upload/server/content/files/160bf87940a54c---ziwoxitotibuwowaf.pdfIn PDF document text
    • http://shreyaghoshal.com/konadnew/userfiles/file/80057580993.pdfIn PDF document text
    • https://bd-sokolovska.eu/userfiles/file/83912364032.pdfIn PDF document text
    • http://neuragen.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160fff8a2a14c5---90533236955.pdfIn PDF document text
    • http://championshipsportsrings.com/clients/23492/File/vururawexiruzutasu.pdfIn PDF document text
    • http://accomplishtheimpossible.com/userfiles_ati/file/kojoxafetosuwuxisomo.pdfIn PDF document text
    • https://fitnessrev.net/wp-content/plugins/super-forms/uploads/php/files/img8vq8u22tu68p2ij6s2fln2q/wegunoraxazevupotuk.pdfIn PDF document text
    • https://www.isgs.org/wp-content/plugins/super-forms/uploads/php/files/0abb544ac0bf8a714acea9699166d6b3/lajisarajasa.pdfIn PDF document text
    • https://veritiesinstitute.com/wp-content/plugins/super-forms/uploads/php/files/efdc1eccf6fd46361fd557cac0d04803/80956462317.pdfIn PDF document text
    • https://michaels-limo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c46ebf111f0---77867349238.pdfIn PDF document text
    • https://bluetact.com/ckfinder/userfiles/files/lisusukanuxorewejide.pdfIn PDF document text
    • https://ncvpte.in/userfiles/file/jefutorok.pdfIn PDF document text
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/nfair3aj6r23jg1fklim8lubf8/161133205.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=f+letter+thingsPDF 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_off0000e5ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5CE 16720 bytes
SHA-256: fc4358b3f8527b7cb32b3ae5c365d1cb30bd08d661f52e4992ee1582a8b770ce
font_01_sfnt_off00011161.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11161 10084 bytes
SHA-256: e0408488a8a3c05319d688d96b1610adf7622e9d82b1d6fd65688df1bdceac4c
font_02_sfnt_off000127ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x127AE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1