Malicious PDF — malware analysis report

Static analysis result for SHA-256 bf4d4ef9ccdb791e…

MALICIOUS

PDF

77.3 KB Created: 2021-09-11 21:32:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: a02097b60ca6eb89f5c2a6abb99c4b63 SHA-1: 0fa07e069efc06c238ee6325e9b9af5d753fea7e SHA-256: bf4d4ef9ccdb791ee32e3bef071f0ebf223fb928c9edd1bc5614bbc8cccd64bc
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many pointing to compromised or disposable hosting, indicating a link farm designed to lure users to malicious sites. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. No scripts were extracted, but the structure itself is the attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://ijacr.net/assets_admin/ckfinder/core/connector/php/uploads/files/20447716312.pdf In PDF document text
    • https://amesmedicalservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130202891bb0---jalezob.pdfIn PDF document text
    • http://smsgurugram.com/miet/assets/files/83221375442.pdfIn PDF document text
    • http://www.xzass.org/ckfinder/userfiles/files/rurubevafuliburuvotuxolox.pdfIn PDF document text
    • http://chinajessie.com/seadata/data/uploads/img/file/163082141292.pdfIn PDF document text
    • https://shunnasato.com/54048400454.pdfIn PDF document text
    • http://goldenmallbiotech.com/upload/files/50863724203.pdfIn PDF document text
    • https://isigakizima.net/img/tmp/file/20167757500.pdfIn PDF document text
    • https://krossi.ru/images/content/files/joxunekimawafu.pdfIn PDF document text
    • http://www.predia.cz/userfiles/file/57571901724.pdfIn PDF document text
    • https://tch.lu/files/files/roparikane.pdfIn PDF document text
    • http://macabrey-luthier.fr/data/Files/nobaxejo.pdfIn PDF document text
    • https://ahreco.com/uploads/news_file/36187274271.pdfIn PDF document text
    • http://vigova.vn/Images_upload/files/99349477722.pdfIn PDF document text
    • https://riolospettacoli.it/filesUploads/file/69916886427.pdfIn PDF document text
    • http://discoveryenglish.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613a6b9bf2e4d---89093793587.pdfIn PDF document text
    • https://sistemagestiondpr.co/userfiles/file/wazasurijixedulej.pdfIn PDF document text
    • http://ithalattagarantibelgesi.com/resimlerfiles/sukemeramajemonur.pdfIn PDF document text
    • https://doitsolutions.co/wp-content/plugins/super-forms/uploads/php/files/3586c2b6cfa4c78e485eb6b88a9b51bd/zudalufefev.pdfIn PDF document text
    • http://hzbmsj.com/images/upload/File/luwuzakiximadusin.pdfIn PDF document text
    • https://dafelia.com/files/kanurujojenamuvubikumuxe.pdfIn PDF document text
    • https://congchungnguyenlieu.vnpec.xyz/uploads/files/zajolasade.pdfIn PDF document text
    • http://www.weilandensemble.nl/ckfinder/userfiles/files/85625608784.pdfIn PDF document text
    • http://studiomistretta.com/userfiles/files/buzoxeb.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=ts3+apk+crackedPDF 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_off0000c631.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC631 10276 bytes
SHA-256: 2bb097db36c50fac4a67ee3b08ce43dc7a96d86985d7e0282d8132d7f8bec1ca
font_01_sfnt_off0000dd7e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD7E 19224 bytes
SHA-256: aff56b6172e9bbeeb17f34f8bbca7968d8ca04b954a34fc29624b9f6b8f8e68e
font_02_sfnt_off00010f98.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F98 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1