Malicious PDF — malware analysis report

Static analysis result for SHA-256 61a4fd887524fda3…

MALICIOUS

PDF

80.1 KB Created: 2021-09-18 02:49:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: 7444e56e9a5fea5ff76e6e9e237ae581 SHA-1: 1d814e14738a9abccda55e9e7b693b09ddb205ff SHA-256: 61a4fd887524fda338244d2911f743bbf9d14b1d1a46f501d8cf1d805a483b7b
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1539 Steal Application Data

The PDF contains multiple external URIs and is flagged as a credential harvesting lure, specifically mentioning MFA or one-time code phishing. The ML classifier and ClamAV detection strongly indicate malicious intent. Although no scripts were explicitly extracted, the PDF structure and embedded URLs suggest it's designed to redirect users to phishing sites, likely leveraging JavaScript for obfuscation or redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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
  • MFA / one-time-code harvesting lure high SE_MFA_LURE
    Document asks for a one-time code, authenticator approval, or MFA confirmation — consistent with credential phishing kits that steal session tokens or abuse multi-factor authentication
  • 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://crewmak.ru/uplcv?utm_term=skype+login+account PDF link annotation
    • https://olivierdaulte.com/ckfinder/userfiles/files/78212340763.pdfIn PDF document text
    • https://rwd1.thadv.com/upload/files/42845898068.pdfIn PDF document text
    • https://www.le-domaine-de-hauterive.fr/ckfinder/userfiles/files/55439697924.pdfIn PDF document text
    • http://ei-windykacja.pl/upload/file/buzalopixonepofudurafi.pdfIn PDF document text
    • http://joelcsimonesq.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/98114335468.pdfIn PDF document text
    • http://terremeraude.com/userfiles/file/warakositilaradut.pdfIn PDF document text
    • https://cashofferoregon.com/wp-content/plugins/formcraft/file-upload/server/content/files/161344bebf0610---wejaxewowolev.pdfIn PDF document text
    • http://oikoscoccatoarchitettura.com/userfiles/files/rogubi.pdfIn PDF document text
    • http://vietdubai.com/userfiles/file/webilawirowerodavegab.pdfIn PDF document text
    • http://rialta.ie/userfiles/files/44139836585.pdfIn PDF document text
    • http://phuocthuan.vn/images/pic/file/36044416429.pdfIn PDF document text
    • https://www.iieng.org/editor/ckfinder/userfiles/files/gatifasaropudafilefa.pdfIn PDF document text
    • http://bargiel.com.pl/ckfinder/userfiles/files/5581042640.pdfIn PDF document text
    • http://cichanski.com/Upload/file/33886863415.pdfIn PDF document text
    • http://ingmarcofaedi.com/userfiles/files/13823164137.pdfIn PDF document text
    • http://www.anglometais.com.br/adm/Editor/ckfinder/userfiles/files/25279414784.pdfIn PDF document text
    • https://datxeninhbinh.com/data/dulieu/files/keduguwisomanovakoxori.pdfIn PDF document text
    • http://tandartsindex.nl/images/uploads/vejudumetawivokitedo.pdfIn PDF document text
    • http://studiomarcheluzzo.it/userfiles/files/64495886132.pdfIn PDF document text
    • https://aletihad-group.com/userfiles/files/megufegawapuxope.pdfIn PDF document text
    • https://glamweddingdesign.com/userfiles/file/54036316164.pdfIn PDF document text
    • http://portableandcool.com/files/files/bobosugusomoxagulodis.pdfIn PDF document text
    • http://dija.lv/public/userfiles/file/22513781415.pdfIn PDF document text
    • http://xn--9p4b29dncp2cc6y.net/upload/fckeditor/file/rufabezexi.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_off0000d28b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD28B 18724 bytes
SHA-256: f08b084a41a90748d29b006d17648882d3bbae73a046b8b1d9e2c5607e9dfe38
font_01_sfnt_off0001028d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1028D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011aa4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11AA4 10664 bytes
SHA-256: 0161fe8fc15aa341f4c3f9f15d3c0ad3becd746e1eb5d2bf7b66593ef6e3d680