Malicious PDF — malware analysis report

Static analysis result for SHA-256 2533d34132e05879…

MALICIOUS

PDF

84.2 KB Created: 2021-09-08 23:23:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: e6b3211ce53112c8922f1c1ef9afd860 SHA-1: 65f6bf243a7d714ce6be179d0a030b24309a5912 SHA-256: 2533d34132e05879a80c1adb40382241dacad4337719ea97a41692d561e0584b
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to redirect users. The presence of multiple external URIs and link farm heuristics strongly suggests a phishing or redirection attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://ilovehikari.com/uploads/files/20866174244.pdf In PDF document text
    • http://anhuishangbiao.com/upload_fck/file/2021-9-4/20210904010330444020.pdfIn PDF document text
    • http://www.bluewhaleline.com/image/upload/File/3182773782.pdfIn PDF document text
    • http://rasmesafar.net/basefile/basefiles/gipuvimamoruririka.pdfIn PDF document text
    • http://somersetcountybar.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/xijonuwukegigavikixasa.pdfIn PDF document text
    • https://www.isnb.co.uk/wp-content/plugins/super-forms/uploads/php/files/c973fc8eff937816605954708c2b979c/87395952976.pdfIn PDF document text
    • http://finchamauto.com/pics/80428449969.pdfIn PDF document text
    • http://mofrantech.com/userfiles/file/68302221941.pdfIn PDF document text
    • http://pamatudarbai.lt/ckfinder/userfiles/files/gegisiwojo.pdfIn PDF document text
    • https://cortemadera.com/wysiwygfiles/file/72694100966.pdfIn PDF document text
    • http://www.siscard.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136dc0c06167---pamifulujefemidoborezilu.pdfIn PDF document text
    • http://ky-auto.com/uploadfile/files/rifopasetamujafuluxa.pdfIn PDF document text
    • http://finproekt-msk.ru/userfiles/file/81851103730.pdfIn PDF document text
    • https://artistaone.co/userfiles/files/96484644240.pdfIn PDF document text
    • https://flims.atelierleuthold.ch/userfiles/files/noxufezikujopunovosab.pdfIn PDF document text
    • https://prtl.pl/userfiles/file/20411103535.pdfIn PDF document text
    • http://lindendirect.com/ckfinder/userfiles/files/50686766805.pdfIn PDF document text
    • http://giasuthanhdat.vn/Images_upload/files/52340702747.pdfIn PDF document text
    • http://prestinoequitacion.com/imagenes/upload/files/laras.pdfIn PDF document text
    • http://omeofest.eu/userfiles/files/92201109513.pdfIn PDF document text
    • http://eyela.kr/uploadfile/fckeditor/file/38919029710.pdfIn PDF document text
    • http://fxlcd.com/upload/file/gifuzonolabefekiboxefu.pdfIn PDF document text
    • https://andymullinscommercial.com/home/andy/public_html/ckfinder/userfiles/files/zowagakiloxirenavasub.pdfIn PDF document text
    • https://amagi.la/wp-content/plugins/formcraft/file-upload/server/content/files/161301a4423cbe---13195131137.pdfIn PDF document text
    • http://mko-yug.ru/wp-content/plugins/super-forms/uploads/php/files/6392f783253832a80ab8df3ec2e07af6/48207518439.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=hide+folder+on+androidPDF 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_off0000e0b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0B0 19916 bytes
SHA-256: f7e1a288af7257963f728ecbee9438952fd953160a204028bb56b0cd9ac25e07
font_01_sfnt_off00011488.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11488 10072 bytes
SHA-256: 8fd3b4129572f922d830feac321ec6c5a32fe2d78d3a6aaad97f1c5563ed7809
font_02_sfnt_off00012aef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12AEF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1