Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb760ea78e232d3c…

MALICIOUS

PDF

77.0 KB Created: 2021-09-19 02:25:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 172c65ffd8183cc42eab35e8af9c75c4 SHA-1: c1e8afc5616b47d9131ccf187627280624a451a2 SHA-256: cb760ea78e232d3c84c516ee798a0dee7782371285d11f566d9c698ccaa9e023
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous embedded URLs pointing to various domains, some of which are associated with compromised CMS uploads or disposable hosting. The primary purpose appears to be directing users to external sites, likely for phishing or to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

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 http://hainfelderteich.at/fanatamig.pdf In PDF document text
    • http://mptech.vn/ckfinder/userfiles/files/98413711416.pdfIn PDF document text
    • http://modernplating.com/userfiles/file/34839318419.pdfIn PDF document text
    • http://traktor-tv.de/sites/default/files/file/seguxuti.pdfIn PDF document text
    • https://wct.goldcrownresort.com/magazine_files/files/51917563471.pdfIn PDF document text
    • http://nakajima-ya.com/upload/save_image/files/41648002218.pdfIn PDF document text
    • http://ziepniekkalns.lv/wp-content/plugins/formcraft/file-upload/server/content/files/1613966b76c49a---21044764263.pdfIn PDF document text
    • https://sipare.com.ar/wp-content/plugins/super-forms/uploads/php/files/a1vq6t0ph53emkbs05tf6kp9df/bikuxilofudoxisogokuvum.pdfIn PDF document text
    • http://skisun.it/userfiles/files/rovemawerovozijoba.pdfIn PDF document text
    • http://imosa.asia/uploads/files/202109060655117341.pdfIn PDF document text
    • https://aykutemlak.com/upload/ckfinder/files/veditagufevidopudido.pdfIn PDF document text
    • https://ccaquebec.com/userupload/files/10471730550.pdfIn PDF document text
    • https://www.hediyevideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fb061c1011---koribikisadapazumujumov.pdfIn PDF document text
    • http://ancheng-medical.com/uploadfile/files/nerurupuzojizekuduwinejuj.pdfIn PDF document text
    • https://rh4-h1tapi-turbo.com/contents/files/27592739400.pdfIn PDF document text
    • http://www.siposferenc.hu/html/kevepowuzusimivasik.pdfIn PDF document text
    • http://leeclinic.kr/userData/board/file/77800058355.pdfIn PDF document text
    • http://venusland.vn/app/webroot/img/files/23680258871.pdfIn PDF document text
    • https://horgaszvelem.hu/ckfinder/userfiles/files/44043583475.pdfIn PDF document text
    • http://cioccolatogallucci.it/userfiles/file/44507420804.pdfIn PDF document text
    • https://vyrukrc.lt/userfiles/file/xazijofesipumitupumezopud.pdfIn PDF document text
    • https://www.educazionesessuale-scuola.ch/ck/ckfinder/userfiles/files/teberikit.pdfIn PDF document text
    • http://aksaaydinlatma.com/img/editor/image/file/60643521888.pdfIn PDF document text
    • https://giorgiosantinelli.it/file/92349097037.pdfIn PDF document text
    • http://rc-modeller.se/images/file///30238121496.pdfIn PDF document text
    • http://grandfiltr.com/files/file/vavos.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=turn+my+tv+on+with+my+phonePDF 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_off0000ca54.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA54 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e26b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE26B 10472 bytes
SHA-256: 0448f94cbc56addbb82ea3aede7b774070442d6acde10a238e56ff2c782ade0c
font_02_sfnt_off0000fa0c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA0C 17120 bytes
SHA-256: 4c562f80edc2611b37ab9892fc31ea31d77d97eb96c6c968e1b583d0295a286b