Malicious PDF — malware analysis report

Static analysis result for SHA-256 83de1395e4a30a80…

MALICIOUS

PDF

92.4 KB Created: 2021-09-08 23:04:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 3675cad4034601531f9f8be7d910ab06 SHA-1: 613e47f35249e4b5d6bb67de2f72dfb627cae52e SHA-256: 83de1395e4a30a801ad5b571250daee57bab5bf0492d1fdf9980df0e7dd5cdc1
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple compromised WordPress sites and disposable hosting, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. The document body is heavily obfuscated and unreadable, but the presence of numerous external links and the heuristic firings confirm the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9726

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://momentous-inst.com/uploads/image/files/mobezozurofejutabu.pdf In PDF document text
    • http://for-rent-antwerp.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613680e12d7ea---16428595294.pdfIn PDF document text
    • http://ipcmanpower.com/admin/style/images/userfiles/file/68424362244.pdfIn PDF document text
    • https://kristaldicarlo.com/userfiles/file/wadewagag.pdfIn PDF document text
    • https://spa-salon.ru/ckfinder/userfiles/files/fosadilatalezebinelolib.pdfIn PDF document text
    • http://notariocprietoa.com/notaria/documentos/files/sifarozikedelajimi.pdfIn PDF document text
    • https://www.almuhja.com/ckfinder/userfiles/files/kifez.pdfIn PDF document text
    • http://xn--3bsx3iw22bmot.com/filespath/files/20210904063628.pdfIn PDF document text
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/rs14smq8vticoj1o6h77iopks7/46807809014.pdfIn PDF document text
    • http://sntaviator.ru/ckfinder/userfiles/files/389202317.pdfIn PDF document text
    • http://xn--aknmedcal-wpbe.com/uploads/file/jagevupisugafemexixibawo.pdfIn PDF document text
    • http://www.predoisiasociatii.ro/wp-content/plugins/formcraft/file-upload/server/content/files/161319032b11df---68011428646.pdfIn PDF document text
    • http://wsm.hk/images/uploadfiles/file/degup.pdfIn PDF document text
    • https://slavica.ru/wp-content/plugins/super-forms/uploads/php/files/8d9fa8572bca259125beb23568f601db/suwuxixemolimuwobonenu.pdfIn PDF document text
    • http://vaynhe.com/upload/files/kowamug.pdfIn PDF document text
    • http://villa-carlshorst.de/sites/default/files/file/54684048208.pdfIn PDF document text
    • https://mimpishio2bet.net/contents/files/wazubikakozezanitudujolu.pdfIn PDF document text
    • http://skinct.com/upload_file/file/Fl202109031212484174.pdfIn PDF document text
    • http://innotack.com/userfiles/files/75070538073.pdfIn PDF document text
    • https://hahapediatric.com/uploads/files/202109040647246280.pdfIn PDF document text
    • https://loyd.rs/images/file/48661059017.pdfIn PDF document text
    • https://newat.ru/wp-content/plugins/super-forms/uploads/php/files/8c41ffe611173f2a9c4ef69ad474565e/sudorejogomun.pdfIn PDF document text
    • http://pcserviszlin.cz/ckfinder/userfiles/files/75682795528.pdfIn PDF document text
    • http://klubalfa.org/img/userfiles/file/34198507803.pdfIn PDF document text
    • http://xpeedon.net/userfiles/file/20210906222118.pdfIn PDF document text
    • https://bomnuocebara.com/quangbasanpham/app/webroot/upload/image/files/14088044455.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=live+map+apkPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e92a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE92A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001013b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1013B 17988 bytes
SHA-256: 24a07b74ee957d6e4a09bf16dd0d553a11b63e28b383b6753734c9134fe8a123
font_02_sfnt_off00011cfd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CFD 18808 bytes
SHA-256: 910693cf5324da551fe686a2b053d0c56bd786af9b1f53bccd95fc766c25c8f3
font_03_sfnt_off00014d85.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14D85 9892 bytes
SHA-256: 89de0ab4544d524369af47e4dd8ffd5efed85ff234d96e3c31371f4bcc80813e