Malicious PDF — malware analysis report

Static analysis result for SHA-256 a963ba528dafa93b…

MALICIOUS

PDF

80.7 KB Created: 2021-09-13 06:10:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: bf05f44b984c335a93ce2090c6da89b9 SHA-1: 77423e804dbad9c642c884dd09d0dd61bcb7a0f6 SHA-256: a963ba528dafa93b58959925863ffc2213a7c0d4aeea3d5833b4370374908ad3
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous external URLs, with one identified as a link farm on disposable hosting, suggesting a phishing or redirection scheme. Although no scripts were explicitly extracted, the PDF structure and heuristic firings point towards techniques used for initial access via spearphishing attachments.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 http://dj-maily.com/uploads/pages/files/66411031108.pdf In PDF document text
    • https://braus.uz/images/shared/file/kajufokuginarajif.pdfIn PDF document text
    • http://asalsold.com/wp-content/plugins/formcraft/file-upload/server/content/files/161374ea26560a---27585184385.pdfIn PDF document text
    • http://dominant.name/userfiles/file/jalimupisesabopezujuxug.pdfIn PDF document text
    • http://juentai.com/userfiles/files/kuwum.pdfIn PDF document text
    • https://pfhotel.gr/ckfinder/userfiles/files/dojuzawalajige.pdfIn PDF document text
    • http://globalcenterhotels.com/bot/ckfinder/uf/files/45594882591.pdfIn PDF document text
    • https://malinaionescu.ro/userfiles/file/81135657266.pdfIn PDF document text
    • https://ymvii.com/admin/upload/files/dunowa.pdfIn PDF document text
    • https://nezrenpin.com/calisma2/files/uploads/dubigakusutodidutiruwid.pdfIn PDF document text
    • https://newsru.md/upload/userfiles/files/vuvoj.pdfIn PDF document text
    • http://www.platformliften.info/wp-content/plugins/formcraft/file-upload/server/content/files/1612f9064294d5---49630722164.pdfIn PDF document text
    • http://mg001.cn/upload_fck/file/2021-9-1/20210901160831880875.pdfIn PDF document text
    • http://bdpq.hungminhits.com/files/uploaded/files/29700053885.pdfIn PDF document text
    • https://littleitalypizzany.com/nbloom/fckuploads/file/77128319414.pdfIn PDF document text
    • https://ruiguoex.com/upfile/files/2021/09/09/doguvuzefobiduwuxumi.pdfIn PDF document text
    • http://anpharma.net/upload/files/95695659625.pdfIn PDF document text
    • https://bititechnika.com/uploads/file/lenadugupojisuxor.pdfIn PDF document text
    • http://rockycheng.com/ckfinder/userfiles/files/38979241473.pdfIn PDF document text
    • http://anshan56.cn/userfiles/file/16309469522064576297.pdfIn PDF document text
    • http://amblesidewindermere.ca/fckuploads/images/file/supifux.pdfIn PDF document text
    • http://locum-system.pl/userfiles/file/vaguvujukesimeve.pdfIn PDF document text
    • http://bamboomfi.com/htdocs/cljr/data/files/fogodux.pdfIn PDF document text
    • http://www.masozilina.sk/ckfinder/userfiles/files/paniwatopo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=crop+pages+in+pdf+onlinePDF 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_off0000d064.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD064 19896 bytes
SHA-256: 84d238492bb4080d9519a78d6e48b99b8bbed6cbc60c527d1f6e8a748783eaaf
font_01_sfnt_off000104b2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104B2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011cc9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CC9 10604 bytes
SHA-256: f6494dbbdb9386c56b336ed0a059a6992ed5ae40e03428c0c0114c332e8b9e04