Malicious PDF — malware analysis report

Static analysis result for SHA-256 753fbd454ecbbc43…

MALICIOUS

PDF

79.4 KB Created: 2021-09-18 13:36:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 9f04ca0465e9ae0b149fe8a9bf2afaed SHA-1: c676e122f50152bcd4348437c8c3bc805291025b SHA-256: 753fbd454ecbbc43afc81532918ddf0fca1fb81393a812a7a644f5b09a6eeaee
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 or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery through these links. The document body is heavily obfuscated and unreadable, providing no direct content clues.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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://ketchas.ru/uplcv?utm_term=stickman+fighter+dragon+shadow PDF link annotation
    • http://beastyenergy.com/userfiles/file/2085245456.pdfIn PDF document text
    • http://interno-kazan.ru/upload/files/14206331428.pdfIn PDF document text
    • http://chukgoobok.com/files/fckeditor/file/76087451706.pdfIn PDF document text
    • http://www.saveurspoitoucharentes.com/admin/ckfinder/userfiles/files/94684151934.pdfIn PDF document text
    • http://sevvalturizm.com/rsm/files/64477266767.pdfIn PDF document text
    • https://waxparadise.pl/userfiles/file/mesegabatinazegufol.pdfIn PDF document text
    • http://xyr59.com/filespath/files/20210915151308.pdfIn PDF document text
    • http://kryotherapie.net/neu/userfiles/file/49148279538.pdfIn PDF document text
    • http://igigeothermal.jp/userfiles/file/nuvewikuzenuwa.pdfIn PDF document text
    • https://abyway.lv/images/ck_images/files/gilubibasakudowokawib.pdfIn PDF document text
    • http://www.primalegal.eu/wp-content/plugins/super-forms/uploads/php/files/mqst0u0jl9np0dj6ut753u3ud4/80234348341.pdfIn PDF document text
    • http://teifsepahan.com/files/file/6728558471.pdfIn PDF document text
    • https://jetaime-shop.com/files/46205500588.pdfIn PDF document text
    • http://bbdecontra.com/userfiles/files/67868253239.pdfIn PDF document text
    • https://mosoptagro.ru/wp-content/plugins/super-forms/uploads/php/files/bac4ebaf32fe6ed8491f5fa17149f9c6/gukitamusezagaxuxasodez.pdfIn PDF document text
    • https://classoft.ro/userfiles/file/90679968158.pdfIn PDF document text
    • http://jtylek.pl/Upload/file/29442078440.pdfIn PDF document text
    • http://marcelponjee.nl/ponjeefiles/file/67079819323.pdfIn PDF document text
    • http://gloteckr.com/upload/editor/file/70656232866.pdfIn PDF document text
    • https://finestblogger.de/wp-content/plugins/super-forms/uploads/php/files/hrtiq0l56a32ks04vc7ifmmecq/57658863624.pdfIn PDF document text
    • http://allamericannursing.com/userfiles/file/51437228504.pdfIn PDF document text
    • http://trainternational.in/wp-content/plugins/formcraft/file-upload/server/content/files/16136950b53781---sopetila.pdfIn PDF document text
    • http://retroldn.com/userfiles/file/lewuzolivu.pdfIn PDF document text
    • http://hongphuc.vn/userfiles/file/wazozukeledi.pdfIn PDF document text
    • http://cokhiminhhien.com/media/ftp/file/wogaxitu.pdfIn PDF document text
    • 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_off0000ce79.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE79 11128 bytes
SHA-256: d8d47642c941505d7366d2c2fe91d547429ff07520b6519099bc091240a3113b
font_01_sfnt_off0000e820.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE820 18612 bytes
SHA-256: 02a4292bed62dd5e380831b9658a828c5f7bf2fa394e0334a444aa34ba68db02
font_02_sfnt_off00011808.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11808 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1