Malicious PDF — malware analysis report

Static analysis result for SHA-256 ae3f3e73736e2071…

MALICIOUS

PDF

70.9 KB Created: 2021-10-01 04:46:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0953259a2d8f6065f2cd9057b3aafd91 SHA-1: 6455a619245e127e7a375b5e5cddc7701f44cc4f SHA-256: ae3f3e73736e2071b4703c8db9b3f88d7fbf65dbb6e7caf5ad969c5ecb02ff98
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent. Although no scripts were explicitly extracted, the nature of the URLs and the heuristic firings point towards a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9909

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://inwebjor.ru/uplcv?utm_term=fnf+download+apk+android
    • https://xn--fct8ml6mwue.tw/uploads/files/gugewizaxalozevod.pdf
    • https://funcarele.com/ckfinder/userfiles/files/gizimokebatu.pdf
    • http://autoscuolemontagna.it/userfiles/files/80258681599.pdf
    • https://edukiya.com/wp-content/plugins/super-forms/uploads/php/files/73c81098ad75c8e9b03410a35ac110ef/wixisefimi.pdf
    • https://hidropomp2008.com/uploads/userfiles/file/wakoloxuperekizaje.pdf
    • https://studiopros.com/userfiles/file/
    • https://gccpay.net/wp-content/plugins/super-forms/uploads/php/files/cca4011fb398a2f6a952a3961a5b2cc5/8031559755.pdf
    • https://dycmc.com/DATA/upload/files/202109141337324476.pdf
    • https://tfnd.org/wp-content/plugins/super-forms/uploads/php/files/20ad967c1330ed82c85d89b55b14619a/89566110349.pdf
    • http://minipit.com/data/files/65111559215.pdf
    • https://www.birdandwildlifeteam.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612efc29bd558---xasunuzokumivitav.pdf
    • http://chatyzvule.cz/uploads/82082578831.pdf
    • http://xinyuemu.net/assets/202109/files/20210901065510273290.pdf
    • https://gosselindesign.com/images/from_fckeditor/fichiers/6696080746.pdf
    • http://utcsp.rustyramone.com/uploads/files/1242470345.pdf
    • https://dhesient.com/media/66933971527.pdf
    • https://verlauf-ekb.ru/admin/ckfinder/userfiles/files/zekonesow.pdf
    • https://cualuoihoanmy.com/uploads/userfiles/file/62211522298.pdf
    • https://www.truesdalepainting.com/wp-content/plugins/formcraft/file-upload/server/content/files/16156244e45381---wimerudezaxekixe.pdf
    • http://ferien-in-zahren.de/images/file/83291402737.pdf
    • http://uyaviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/161304a94b2535---84371743612.pdf
    • https://greenlakepaint.com/ckfinder/userfiles/files/nulaxujuregidasu.pdf
    • http://c-amc.com/upload/files/zimazuwepawabapo.pdf
    • https://transturist.ba/ckeditor/ckfinder/files/files/melomometiru.pdf
    • https://argekaucuk.com/nbg/upload/files/mebobar.pdf
    • http://perlawarmii.pl/userfiles/file/tuposelim.pdf
    • https://bisnismedsos.com/userfiles/file/fesafozam.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_off0000b605.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB605 16792 bytes
font_01_sfnt_off0000ce1c.bin
0ece86e99c69a9c944200235b30e62521f77735fdcc8d430959f5657d9060240
pdf-font-stream PDF embedded font (sfnt) at offset 0xCE1C 10248 bytes
font_02_sfnt_off0000e52c.bin
ca4a591ba96022e32ccce51deff34d2f89d6abcae2814fc33c2f9c938c693a8e
pdf-font-stream PDF embedded font (sfnt) at offset 0xE52C 15908 bytes